Answer: 12
Step-by-step explanation: V of prism = S of triangle*Height of prism
height of prism is 30
S of triangle = a/2*<em>h</em>( a =18 cm)
3240=30*(18/2)*<em>h</em>
<em>h</em>=3240/(9*30)=12
Answer:
504 cm squared
Step-by-step explanation:
To find the surface area, find the area of the square base and add it to the area of each triangle face.
Find the area of the base by multiplying base length by base length.
Here the base is 12 x 12 = 144.
Find the area of each triangle face by multiplying 1/2 * b*h.
Here the area is 1/2 * 12 * 15 = 90. Since there are 4 faces, the total area is 4 * 90 = 360.
Together the surface area is 360 + 144 = 504.
This requires us to find the number of permutations of 6 different bands taken 2 at a time:
Answer:
77
Step-by-step explanation:
84/12=7
so
7*11= 77
Answer:
15.6
Step-by-step explanation:
First, multiply the midpoint of each class by its frequency, as follows:
Class midpoint frequency midpoint*frequency
0-9 4.5 24 4.5*24 = 108
10-19 14.5 20 14.5*20 = 290
20-29 24.5 32 24.5*32 = 784
Total 76 1182
The mean is computed as the division between the addition of the "midpoint*frequency" column by the addition of "frequency" column.
mean = 1182/76 ≈ 15.6
