20% of 60 is 12
60/300 = 20%
The friend is incorrect because that is 20% of 300 not 60
There will be eight marbles on the 9th line
<span>1*441 & 3*147 & 7*63 & 9*41 &21*21 are all factor pairs of 441
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21&21 have the smallest sum and would make for the smallest perimeter
Answer:l=21 w=21
(60,4)(120,8)
slope = (8 - 4) / (120 - 60) = 4/60 = 1/15 <== the constant of proportionality is the slope
Perimeter is when you add all the sides together...but oh, no! There are two sides missing! So we have to find it. The horizontal like could be x and the vertical, the y. x would be 3 because one side is 7 and the other side is 4, so if we subtract them, we get 3. Same for the vertical, the y would be 3. (3+3=6)
Now we could add all sides to get the last choice, or 26 cm.