If I pile grapefruit in a pyramid with 1 grapefruit in the first layer, 4 in the second layer (from the top), 9 in the third layer, and 16 in the fourth layer, how many grapefruit will I need to make a pile with 10 layers?
Brilliant answer Ariaana! That's exactly what I came up with. Rosemary - Think about the question again... the 10th row would be 10 by 10 ... 10X10=100.
You will need 427 grapefruits in total, and the 10th layer alone will be 112 grapefruits.
ReplyDeleteYou will need 385 grapefruit!
ReplyDelete(1 + 2squared + 3 squared + 4 squared + 5 squared + 6 squared + 7 squared + 8 squared + 9 squared + 10 squared ) = 385
Brilliant answer Ariaana! That's exactly what I came up with.
ReplyDeleteRosemary - Think about the question again... the 10th row would be 10 by 10 ... 10X10=100.
you would need 385 grapefruit because you square every number until 10 and 1+4+9+16+25+36+49+72+81+100=385
ReplyDeleteThank you for the good comments. The answer is 385.
ReplyDelete