Using the compound interest formula,
572.86=287,50(1+i)^8
(1+i)^8=572.86/287.50=1.992557
1+i=(1.992557)^(1/8)=1.0899996
=>
i=1.0899996-1=9%
Note: This problem can also be solved in the head using the rule of 72.
Since after 8 years, the amount is roughly doubled, we can say that the interest rate is approximately 72/8=9%
28 because a constant is a number that doesn't have x attached to it.hope this helps
4.Answer is $2.55
5.Answer is $32.01
$10.50 gets taken off the original price. I divided $42 by 4 because 25 is 1/4th of 100. This got me $10.50. The original price ($42) minus $10.50 equals $31.50. So the item sells for $31.50!!!!
14-3=11 So she needed to cut of 11 yards of fabric.
