Answer:
1) C: 113 m
2) C: 572.3 m²
3) B: 61.2 cm²
4) A: $2.2
6) C: 756 yd³
8) D: 3402 mm²
9) A: 25x + 125 < 500
Step-by-step explanation:
1) Formula for circumference of circle is;
C = 2πr
radius; r = 18 m
C = 2π × 18
C ≈ 113 m
2) Formula for area of a circle is;
A = πr²
Here we have diameter; d = 27
Thus, radius; r = 27/2 = 13.5 m
A = π × 13.5²
A = 3.14 × 13.5²
A ≈ 572.3 m²
3) The diameter of the semicircle is parallel to the base of the rhombus. Thus, diameter; d = 7 cm
Thus, r = 7/2 = 3.5 cm
Area of semi circle = ½πr² = ½ × π × 3.5² = 19.2 cm²
Area of rhombus = base x height = 7 × 6 = 42 cm²
Total area of object = 42 + 19.2 = 61.2 cm²
4) Cost of banana per pound = $0.4 per pound
Amount of banana bought = 5.5 pound
Amount spent = 0.4 × 5.5 = $2.2
6) Volume of triangular prism is;
V = ½bhl
b = 12 yd
h = 7 yd
L = 18 yd
Thus;
V = ½ × 12 × 7 × 18
V = 756 yd³
8) Volume of cuboid at the base;
V1 = lbh = 25 × 9 × 9 = 2025 mm²
Volume of cuboid at top;
V2 = 9 × 9 × 9 = 729 mm²
Volume of triangular prism;
V3 = ½bhl = ½ × 9 × 9 × (25 - 9) = ½ × 81 × 16 = 648 mm²
Total volume = 2025 + 729 + 648 = 3402 mm²
9) Cost per class; $25 per class
Charge for the supplies = $125
He doesn't want to spend more than $500.
Thus;
25x + 125 < 500
