Question

A set of telephone poles is stacked in a pile, 8 layers high. The top layer consists of 20 telephone

poles. The next layer down consists of 24 telephone poles. The third layer consists of 28
telephone poles. If this pattern continues for the remaining 5 layers, how many telephone poles
are in the pile?
A. 224
B. 244
C. 252
D. 272

Answer 1

D. 272 poles

Step-by-step explanation:

We are given that:

The top layer has 20 poles, the next down one has 24 poles and the third one has 28 poles

We can note that each layer has 4 poles more that the one above it

Based on this, we can get the number of poles in each layer as follows:

Top layer has 20 poles

Second one has 20 + 4 = 24 poles

Third one has 24 + 4 = 28 poles

Fourth one has 28 + 4 = 32 poles

Fifth one has 32 + 4 = 36 poles

Sixth one has 36 + 4 = 40 poles

Seventh one has 40 + 4 = 44 poles

Eighth one has 44 + 4 = 48 poles

Now, we can get the total number of poles by adding the poles in all layers

This is done as follows:

Total number of poles = 20 + 24 + 28 + 32 + 36 + 40 + 44 + 48

Total number of poles = 272 poles

Hope this helps :)