Showing 141–160 of 161

Q141.The solution set of equation x-3 =4?

Medium
A 7
B 15
C 19
D 34
Algebraic Expressions PPSC

Correct Answer: A

Solving for x: x - 3 = 4 => x = 4 + 3 = 7.

Q142.The sum of four consecutive even numbers is 292 what is the smallest number?

Medium
A 66
B 68
C 70
D 72
Algebraic Expressions PPSC

Correct Answer: C

Let the consecutive even numbers be x, x+2, x+4, x+6. Sum = 4x + 12 = 292 => 4x = 280 => x = 70. Smallest is 70.

Q143.What is the additive inverse of matrix? Matrix = [ -7 8 ] [ 6 3 ]

Medium
A [ 7 -8 ] [ -6 -3 ]
B [ -7 -8 ] [ 6 -3 ]
C [ 7 8 ] [ 6 3 ]
D [ -7 8 ] [ -6 -3 ]
Linear Equations PPSC

Correct Answer: A

The additive inverse of a matrix A is -A, where each element is negated. This yields [ 7 -8 ] [ -6 -3 ].

Q144.(a² - b²) = ?

Medium
A (a + b)(a - b)
B A + b
C A - b
D B - a
Algebraic Expressions PPSC

Correct Answer: A

The algebraic identity for the difference of two squares is: a² - b² = (a - b)(a + b).

Q145.If x + 1/x = 3, find the value of x³ + 1/x³.

Medium
A 9
B 18
C 21
D 27
Algebraic Expressions PPSC

Correct Answer: B

x³ + 1/x³ = (x + 1/x)³ − 3(x + 1/x) = 3³ − 3*3 = 27 − 9 = 18.

Q146.If R = xS⁴, and R = 6 when S = 5, find the value of R when S = 8.

Medium
A 39.3
B 20.5
C 32.8
D 52.4
Algebraic Expressions PPSC

Correct Answer: A

R = xS⁴. At S=5, R=6 => 6 = x * 625 => x = 6/625. When S=8, R = (6/625) * (8⁴) = 39.3 approx.

Q147.What is the value of 8.73 × 8.73 × 8.73 + 4.27 × 4.27 × 4.27?

Medium
A 827.5
B 832.0
C 742.57
D None of these
Algebraic Expressions PPSC

Correct Answer: C

Using the algebraic expansion a³ + b³ = (a+b)((a+b)² - 3ab) where a = 8.73 and b = 4.27, we get a+b = 13 and ab = 37.2671. Sum = 13 × (169 - 111.8013) = 742.57 approx.

Q148.Does the parabola y = 2x² - 13x + 5 have a tangent whose slope is -1? If so, what is its equation?

Medium
A y = -x - 13
B y = 2x + 2
C y = x² - 1
D None of these
Linear Equations PPSC

Correct Answer: A

Slope dy/dx = 4x - 13 = -1 => x = 3. At x=3, y = 2(9) - 13(3) + 5 = -16. Tangent equation: y + 16 = -1(x - 3) => y = -x - 13.

Q149.Solve: 5x − {3x + [4x − 2x]}

Medium
A 7
B 8.67
C 9
D 0
Algebraic Expressions PPSC

Correct Answer: D

5x - [3x + 2x] = 5x - 5x = 0.

Q150.What is the value of x in the equation 3x − 2 = 24?

Medium
A 7
B 8
C 8.67
D 9
Algebraic Expressions PPSC

Correct Answer: C

3x = 26 => x = 26/3 ≈ 8.67.

Q151.Expand the expression: (x + 4)(x - 2)

Medium
A 2x^2 - 5x + 6
B x^2 + 2x - 8
C x^2 - 9
D x^2 + 1
Algebraic Expressions PPSC

Correct Answer: B

(x + 4)(x - 2) = x^2 - 2x + 4x - 8 = x^2 + 2x - 8.

Q152.What are the roots of the equation: x^2 + x - 2 = 0?

Medium
A x = -2, x = -1
B x = -2, x = 1
C x = 2, x = 2
D None of these
Algebraic Expressions PPSC

Correct Answer: B

Factorize: (x + 2)(x - 1) = 0. So, roots are x = -2 and x = 1.

Q153.What is the numerical coefficient in the algebraic term 6X^2Y?

Medium
A 6
B 3
C 2
D 4
Algebraic Expressions PPSC

Correct Answer: A

The numerical coefficient is the constant multiplier of the variables, which is 6.

Q154.What are the factored roots of the expression: X² - 5X + 6?

Medium
A (x-2)(x-3)
B (x-3)(x-3)
C (x+2)(x-3)
D None of these
Algebraic Expressions PPSC

Correct Answer: A

We factor 6 into -2 and -3 (whose sum is -5): (x-2)(x-3) = x² - 5x + 6.

Q155.Which of the following represents the commutative property of addition?

Medium
A A+B = B+A
B A+B = B+B
C A+B = A-B
D None of these
Algebraic Expressions PPSC

Correct Answer: A

The commutative property of addition states that numbers can be added in any order and yield the same sum: A + B = B + A.

Q156.What is the expansion of A(b+c)?

Medium
A ab+cb
B ab+ab
C ab+ac
D None of these
Algebraic Expressions PPSC

Correct Answer: C

By applying the distributive property of multiplication over addition, we get: A(b+c) = ab + ac.

Q157.What is (a² - b²) equal to?

Medium
A (a-b)(a-b)
B 2(a+b)
C (a+b)(a-b)
D None of these
Algebraic Identities PPSC

Correct Answer: C

The difference of squares formula states: a² - b² = (a+b)(a-b).

Q158.What is the value of 6² - 4²?

Medium
A 15
B 20
C 25
D 30
Algebraic Expressions PPSC

Correct Answer: B

Calculated as: 6² - 4² = 36 - 16 = 20.

Q159.Solve for x in the equation: 2x + 5 = 13.

Medium
A X = 3
B X = 5
C X = 4
D X = 6
Algebraic Expressions PPSC

Correct Answer: C

Subtract 5 from both sides: 2x = 8. Divide both sides by 2: x = 4.

Q160.Simplify the expression: (7 - √2)(7 + √2).

Medium
A 45
B 47
C 49
D 51
Algebraic Expressions PPSC

Correct Answer: B

Using the difference of squares identity (a - b)(a + b) = a² - b²: (7)² - (√2)² = 49 - 2 = 47.