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Penn stacks all of his snowballs in a square pyramid......

Which could not be the number of snowballs penn has?

Penn stacks all of his snowballs in a square pyramid...... Which could not be the-example-1
User Grant
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2 Answers

4 votes

Answer:

i think its 25

Explanation:


4 votes

Answer:

The correct option is B.

Explanation:

The number of snowballs in n layers of square pyramid is given by


P(n)=P(n-1)+n^2


P(1)=P(1-1)+1^2


P(1)=P(0)+1=1


P(2)=P(2-1)+2^2


P(2)=P(1)+4\Rightarrow 1+4=5


P(3)=P(3-1)+3^2


P(3)=P(2)+9\Rightarrow 5+9=14


P(4)=P(4-1)+4^2


P(4)=P(3)+16\Rightarrow 14+16=30


P(5)=P(5-1)+5^2


P(5)=P(4)+25\Rightarrow 30+25=55

The values of P(n) are 1, 5, 14, 30, 55 ,....

25 could not be the number of snowballs penn has.

Therefore the correct option is B.

User Russell Zornes
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5.8k points