Answer:
42
Step-by-step explanation:
x/3+12 = 26
Multiply everything by 3 to eliminate the fraction
x+36=78
subtract 36 on both sides
x=42
42/3=14
14+12=26
Detailed Answers:
Volume of a Sphere (V) = 4/3 πr^3
1. Diameter (d) = 21.6 cm
Radius (r) = 21.6/2 = 10.8 cm
Therefore,
= 4/3 πr^3
= 4/3 * 22/7 * (10.8)^3
= 4/3 * 22/7 * 1259.712
= 88/21 * 1259.712
=> 5278.79
Volume (V) = 5278.79 cm^3
2. Diameter (d) = 16 cm
Radius (r) = 16/2 = 8 cm
Therefore,
= 4/3 πr^3
= 4/3 * 22/7 * (8)^3
= 4/3 * 22/7 * 512
= 88/21 * 512
=> 2145.52
Volume (V) = 2145.52 cm^3
3. Diameter (d) = 24 cm
Radius (r) = 24/2 = 12 cm
Therefore,
= 4/3 πr^3
= 4/3 * 22/7 * (12)^3
= 4/3 * 22/7 * 1728
= 88/21 * 1728
=> 7241.14
Volume (V) = 7241.14 cm^3
4. Diameter (d) = 6 cm
Radius (r) = 6/2 = 3 cm
Therefore,
= 4/3 πr^3
= 4/3 * 22/7 * (3)^3
= 4/3 * 22/7 * 27
= 88/21 * 27
=> 113.14
Volume (V) = 113.14 cm^3
<u>Answer: </u>
Option (c)
The average speed between 2.8 km and 4.2 km is 42 km/h
<u>Explanation:</u>
Given, the distance between 2.8 km and 4.2 km is 4.2 - 2.8 = 1.4 km
Time (in hours) between 2.8 km and 4.2 km
= 0.084 – 0.051
= 0.033 hr
Speed =
Speed = 
Speed = 42.4 km/hr = 42 km/h (rounded to nearest)
Therefore, the average speed between 2.8 km and 4.2 km is 42 km/hr
Hence, Option (C) is correct
Max will be missing $1.78 in his account. Is that one of the fee choices?