Answer:
The sum of the age of pupils is 81
Step-by-step explanation:
Let sum of age of 18pupils = x
Average ages = 4.5
Average = total/no. of pupil
4.5 = x/18
x = 81
Since the number before the number in the tenth place (7) is greater than 5 (8), you will be rounding up. So your answer is 9.80
Which part do you need help on?
The answer to your problem is 58/90
Answer:
Step-by-step explanation:
LA, Laterial Surface Area, is the lateral surface area of a pyramid. In this case, it is the sum of five triangles with base of 12cm and height that can be calculated as follow:
height^2 = 8.26^2 + 20^2 = 468.23
height = 21.64cm
LA = 5*1/2*12*21.64
= 649.2cm^2
SA, Surface Area, is the sum of LA and base area.
Base area = 5*1/2*12*8.26 = 247.8cm^2
SA = 649.2 + 247.8 =897cm^2
Volume, V = 1/3 * base area * height
= 1/3 * 247.8 * 20
= 1652cm^3