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Mathematics
UTME / JAMB 2025
Logarithms
Solution
Simplify - log\(_{10}\) 0.00001.
A
-5
B
-4
C
5
D
4
medium Difficulty
Verified Correct Answer: Option C
Step-by-Step Mathematical Solution
0.00001 = 10\(^{-5}\),
so, log\(_{10}\)(10\(^{-5}\)) = - 5.
Then -(-5) = 5.
Source: WAEC / JAMB / NECO Classroom Archive (Record #74163)
Mathematics
WAEC / WASSCE 2025
Logarithms
Solution
If log\(_{10}\)x = 2.3675 and log\(_{10}\)y = 2.9738, what is the value of x + y, correct to three significant figures
A
0.118
B
0.903
C
0.117
D
0.944
medium Difficulty
Verified Correct Answer: Option A
Step-by-Step Mathematical Solution
log\(_{10}\)x = 2.3675 ⇒ x = 10\(^{2.3675}\) ⇒ x ≈ 0.02331
log\(_{10}\)y = 2.9738 ⇒ y = 10\(^{2.9738}\) ⇒ y ≈ 0.09414
∴ x + y = 0.02331 + 0.09414 = 0.11745 = 0.118 (3 s.f.)
Source: WAEC / JAMB / NECO Classroom Archive (Record #75851)
Mathematics
UTME / JAMB 2025
Surds
Solution
Solve for y in \(\sqrt{75}\) - \(\sqrt{12}\) + \(\sqrt{27}\) = y\(\sqrt{3}\)
A
\(4\sqrt{3}\)
B
\(5\sqrt{3}\)
C
\(3\sqrt{3}\)
D
\(6\sqrt{3}\)
medium Difficulty
Verified Correct Answer: Option D
Step-by-Step Mathematical Solution
\(\sqrt{75} - \sqrt{12} + \sqrt{27} = y\sqrt{3}\)
Simplify each term:
- \(\sqrt{75} = \sqrt{25 \times 3} = 5\sqrt{3}\)
- \(\sqrt{12} = \sqrt{4 \times 3} = 2\sqrt{3}\)
- \(\sqrt{27} = \sqrt{9 \times 3} = 3\sqrt{3}\)
Substitute: \(5\sqrt{3} - 2\sqrt{3} + 3\sqrt{3} = y\sqrt{3}\)
Combine like terms: \((5 - 2 + 3)\sqrt{3} = y\sqrt{3}\)
\(6\sqrt{3} = y\sqrt{3}\)
Thus, y = 6
Source: WAEC / JAMB / NECO Classroom Archive (Record #74194)
Mathematics
UTME / JAMB 2025
Number and Numeration
Solution
Express \(\sqrt[4]{0.16}\) in standard form
A
2 \(\times 10^{-\frac{1}{2}}\)
B
2 \(\times 10^2\)
C
2 \(\times 10^{-2}\)
D
2 \(\times 10^{\frac{1}{2}}\)
medium Difficulty
Verified Correct Answer: Option A
Step-by-Step Mathematical Solution
\(\sqrt[4]{0.16} = (0.16)^{\frac{1}{4}} = (16 \times 10^{-2})^{\frac{1}{4}} = 2 \times 10^{-\frac{1}{2}}\)
Source: WAEC / JAMB / NECO Classroom Archive (Record #74192)
Mathematics
UTME / JAMB 2025
Fractions, Decimals, Percentages & Approximation
Solution
A banker spent \(\frac{1}{5}\) of his salary on shirts, \(\frac{1}{3}\) of the remainder on transport, and kept the rest for contingencies. What fraction was left
A
\(\frac{6}{15}\)
B
\(\frac{8}{15}\)
C
\(\frac{7}{15}\)
D
\(\frac{4}{5}\)
medium Difficulty
Verified Correct Answer: Option B
Step-by-Step Mathematical Solution
Let the salary be \( S \).
Amount spent on shirts:
\(\text{Shirts} = \frac{1}{5} S\)
Remainder after shirts:
\(\text{Remainder} = S - \frac{1}{5} S = \frac{4}{5} S\)
Amount spent on transport:
\(\text{Transport} = \frac{1}{3} \left( \frac{4}{5} S \right) = \frac{4}{15} S\)
Remainder after transport:
\(\text{Remainder} = \frac{4}{5} S - \frac{4}{15} S = \frac{12}{15} S - \frac{4}{15} S = \frac{8}{15} S\)
Thus, the fraction left is: \(\frac{8}{15}\)
Source: WAEC / JAMB / NECO Classroom Archive (Record #74160)
Mathematics
UTME / JAMB 2025
Sets & Set Operations
Solution
The set {1,2,3,4,5} is equivalent to
A
{2,3,1,4}
B
{1,2,3,4,5,5}
C
{1,2,3,4}
D
{4,3,1,5,2}
medium Difficulty
Verified Correct Answer: Option D
Step-by-Step Mathematical Solution
Two or more sets are said to be equivalent when they contain equal elements, denoted by ≡
Original: {1,2,3,4,5}. ≡ {4,3,1,5,2}
Source: WAEC / JAMB / NECO Classroom Archive (Record #74091)
Mathematics
UTME / JAMB 2025
Sets & Set Operations
Diagram
Solution
In the Venn diagram above, the shaded region is
Attached Figure / Diagram
A
(P \(\cap\) Q)' \(\cap\) R
B
(P \(\cap\) Q) \(\cup\) R)
C
(P \(\cup\) Q) \(\cap\) R
D
(P U R)' \(\cap\) Q
medium Difficulty
Verified Correct Answer: Option D
Step-by-Step Mathematical Solution
The Venn diagram has three overlapping circles labeled P, Q, and R.
The shaded region has cross-hatching and covers only the part that belongs to Q but not to P or R (the exclusive part of Q outside the overlaps with P and R).
In set notation, the shaded region is \( Q \cap (P \cup R)^c \)
Source: WAEC / JAMB / NECO Classroom Archive (Record #74198)
Mathematics
UTME / JAMB 2025
Matrices and Determinants
Solution
Find the sum of the entries in the inverse of \(\begin{bmatrix} 1 & 2 \\ 3 & 5 \end{bmatrix}\)
A
1
B
-1
C
2
D
0.5
medium Difficulty
Verified Correct Answer: Option B
Step-by-Step Mathematical Solution
Let the matrix be \(A = \begin{bmatrix} 1 & 2 \\ 3 & 5 \end{bmatrix}\)
The determinant of \(A\) is calculated as follows:
\(\text{Determinant} = 1 \cdot 5 - 2 \cdot 3 = 5 - 6 = -1\)
To find the inverse of \(A\), we first determine the adjoint matrix:
\(\text{Adjoint} = \begin{bmatrix} 5 & -2 \\ -3 & 1 \end{bmatrix}\)
The inverse is given by
\(A^{-1} = \frac{1}{\text{Determinant}} \cdot \text{Adjoint} = \frac{1}{-1} \begin{bmatrix} 5 & -2 \\ -3 & 1 \end{bmatrix} = \begin{bmatrix} -5 & 2 \\ 3 & -1 \end{bmatrix}\)
Next, we calculate the sum of the elements in the inverse matrix:
\(\text{Sum} = -5 + 2 + 3 + (-1) = -1\)
Source: WAEC / JAMB / NECO Classroom Archive (Record #74102)
Mathematics
UTME / JAMB 2025
Matrices and Determinants
Solution
If I is a 2 × 2 identity matrix, find the determinant of the matrix.
A
1
B
2
C
-1
D
0
medium Difficulty
Verified Correct Answer: Option A
Step-by-Step Mathematical Solution
The 2\times2 identity matrix is \(I_2 = \begin{pmatrix} 1 & 0 \\0 & 1 \end{pmatrix}\)
Determinant = (1)(1) - (0)(0) = 1.
Source: WAEC / JAMB / NECO Classroom Archive (Record #74152)
Mathematics
UTME / JAMB 2025
Matrices and Determinants
Solution
The determinant of the matrix \(A = \begin{pmatrix} -2 & 3 & 1 \\ p & 2 & 1 \\ 1 & 4 & 2\end{pmatrix}\) is -5. Find the value of p.
A
0
B
2
C
3
D
1
medium Difficulty
Verified Correct Answer: Option C
Step-by-Step Mathematical Solution
Given the matrix \(A = \begin{pmatrix} -2 & 3 & 1 \\ p & 2 & 1 \\ 1 & 4 & 2 \end{pmatrix}\) the determinant is set to \(-5\):
\(\text{det}(A) = -2 \begin{vmatrix} 2 & 1 \\ 4 & 2 \end{vmatrix} - 3 \begin{vmatrix} p & 1 \\ 1 & 2 \end{vmatrix} + 1 \begin{vmatrix} p & 2 \\ 1 & 4 \end{vmatrix}\)
Calculating the \(2 \times 2\) determinants:
1. \( \begin{vmatrix} 2 & 1 \\ 4 & 2 \end{vmatrix} = 0 \)
2. \( \begin{vmatrix} p & 1 \\ 1 & 2 \end{vmatrix} = 2p - 1 \)
3. \( \begin{vmatrix} p & 2 \\ 1 & 4 \end{vmatrix} = 4p - 2 \)
So, \(\text{det}(A) = -3(2p - 1) + (4p - 2) = -6p + 3 + 4p - 2 = -2p + 1\)
Setting this equal to \(-5\): \(-2p + 1 = -5\)
Solving for \( p \): \(-2p = -6 \implies p = 3\)
Thus, the value of \( p \) is 3
Source: WAEC / JAMB / NECO Classroom Archive (Record #74153)
Mathematics
UTME / JAMB 2025
Matrices and Determinants
Solution
Given that \(P = \begin{pmatrix} 1 & 3 \\ 2 & -5 \end{pmatrix}\) and Q = \(\begin{pmatrix} 3 & -7 \\ 1 & 2 \end{pmatrix}\) . Find P + 2Q
A
\(\begin{pmatrix} 7 & -11 \\ 4 & -1 \end{pmatrix}\)
B
\(\begin{pmatrix} 7 & -11 \\ 4 & -9 \end{pmatrix}\)
C
\(\begin{pmatrix} -7 & 11 \\ -4 & -1 \end{pmatrix}\)
D
\(\begin{pmatrix}11 & -7 \\ 4 & -1 \end{pmatrix}\)
medium Difficulty
Verified Correct Answer: Option A
Step-by-Step Mathematical Solution
Given \(P = \begin{pmatrix} 1 & 3 \\ 2 & -5 \end{pmatrix}, \quad Q = \begin{pmatrix} 3 & -7 \\ 1 & 2 \end{pmatrix}\)
we need to find \(P + 2Q\).
First, calculate \(2Q\): \(2Q = 2 \begin{pmatrix} 3 & -7 \\ 1 & 2 \end{pmatrix} = \begin{pmatrix} 2 \cdot 3 & 2 \cdot -7 \\ 2 \cdot 1 & 2 \cdot 2 \end{pmatrix} = \begin{pmatrix} 6 & -14 \\ 2 & 4 \end{pmatrix}\)
Now add \(P\) and \(2Q\):
\(P + 2Q = \begin{pmatrix} 1 & 3 \\ 2 & -5 \end{pmatrix} + \begin{pmatrix} 6 & -14 \\ 2 & 4 \end{pmatrix} = \begin{pmatrix} 1 + 6 & 3 + (-14) \\ 2 + 2 & -5 + 4 \end{pmatrix}\)
Calculating each entry, we find:
\(= \begin{pmatrix} 7 & -11 \\ 4 & -1 \end{pmatrix}\)
Thus, the result of \(P + 2Q\) is \(\begin{pmatrix} 7 & -11 \\ 4 & -1 \end{pmatrix}\)
Source: WAEC / JAMB / NECO Classroom Archive (Record #74196)
Mathematics
UTME / JAMB 2025
Financial Arithmetic
Solution
A car dealer bought a used car for ₦270,000 and spent ₦70,000 to refurbish it. He later sold the car for ₦490,000. What was the percentage profit?
A
30%
B
35%
C
25%
D
45%
medium Difficulty
Verified Correct Answer: Option D
Step-by-Step Mathematical Solution
Total cost = 270,000 + 70,000 = 340,000.
Profit = 490,000 - 340,000 = 150,000.
Percentage profit = (\(\frac{150,000}{340,000}\)) \times 100
= (\(\frac{15}{34}\)) \times 100 ≈ 44.12%. The closest option is 45%
Source: WAEC / JAMB / NECO Classroom Archive (Record #74156)
Mathematics
UTME / JAMB 2025
Financial Arithmetic
Solution
An amount of # 600,000.00 was realized when a principal y was saved for 5% simple interest for 4 years, find the value of y
A
# 570,000
B
# 500,000
C
# 300,000
D
# 400,000
medium Difficulty
Verified Correct Answer: Option B
Step-by-Step Mathematical Solution
Using \(A = P(1 + rt)\)
Substituting known values:
\(600,000 = y \left(1 + 0.05 \times 4\right)\)
\(600,000 = y \times 1.20\)
Solving for \( y \):
\(y = \frac{600,000}{1.20} = 500,000\)
Thus, the principal amount is # 500,000
Source: WAEC / JAMB / NECO Classroom Archive (Record #74170)
Mathematics
UTME / JAMB 2025
Variations
Solution
Y is partly constant and partly varies as x. When x = 3, y = 7 and when x = 5, y = 11. Find the constants of variation.
A
2,3
B
1,2
C
3,2
D
3,4
medium Difficulty
Verified Correct Answer: Option B
Step-by-Step Mathematical Solution
Form: y = a + b x.
7 = a + 3b. - - - - - - - 1
11 = a + 5b. - - - - - - 2
Solve both equations using the elimination method
Subtract: 4 = 2b ⇒ b = 2.
put b = 2 into eqn 1
a + 6 = 7 ⇒ a = 1. Constants a = 1 (constant part), b = 2 (variation constant).
Source: WAEC / JAMB / NECO Classroom Archive (Record #74100)
Mathematics
UTME / JAMB 2025
Variations
Solution
A varies directly as b\(^2\) when A = 4, b = 1. Find A when b = 2
A
12
B
14
C
16
D
11
medium Difficulty
Verified Correct Answer: Option C
Step-by-Step Mathematical Solution
A ∝ b\(^2\) so A = k b\(^2\).
Substitute: 4 = k · 1\(^2\),
k = 4.
When b = 2,
A = 4 · 4 = 16.
Source: WAEC / JAMB / NECO Classroom Archive (Record #74151)