A 31.4
B 62.8
C 125.6
D 314
Explanation: Area = (θ/360)πr² = (36/360)(3.14)(100) = 0.1 × 314 = 31.4.
A 3/10
B 6/9
C 6/20
D 3/20
Explanation: 2/5 × 3/4 = 6/20 = 3/10. But as written, 6/20 is correct.
Explanation: Perimeter = 2(l+w) = 2(12+5) = 34.
Explanation: (-2)³ + (-2)² = -8 + 4 = -4.
Explanation: 1/2 + 1/3 = 3/6 + 2/6 = 5/6.
A 94.2
B 188.4
C 282.6
D 376.8
Explanation: Volume = πr²h = 3.14 × 9 × 10 = 282.6.
Explanation: (2x)² = 4x².
Explanation: 60% of 250 = 0.60 × 250 = 150.
Explanation: (2+3)² = 5² = 25.
Explanation: GCD(24,36) = 12.
Explanation: 15% of 300 = 0.15 × 300 = 45.
A x = 2 or x = 8
B x = 2 only
C x = 8 only
D x = 3 or x = 5
Explanation: x - 5 = 3 or x - 5 = -3, so x = 8 or x = 2.
Explanation: Area = ½ × d₁ × d₂ = ½ × 8 × 6 = 24.
Explanation: 11% of 500 = 0.11 × 500 = 55.
Explanation: 3x/6 + 2x/6 = 10, 5x/6 = 10, x = 12.
Explanation: Average = (3+7+11+15+19)/5 = 55/5 = 11.
Explanation: 0.6 × 0.5 = 0.30 = 0.3.
Explanation: 12 + 4y = 24, 4y = 12, y = 3.
Explanation: 25% of 120 = 0.25 × 120 = 30.