Bess has $2.80 in quarters and dimes. the number of dimes is 7 less than the number of quarters. find the number of quarters and dimes

3 dimes and 10 quarters

Step-by-step explanation:

If you add 7 dimes, then the number of dimes and quarters is the same, and the total increases to $3.50. A dime and a quarter have a value together of $0.35. Since there are equal numbers, the value $3.50 must be made up of some quantity of groups with a value of $0.35. That number of groups must be ...

... $3.50/$0.35 = 10

Thus, there are 10 quarters and 10-7 = 3 dimes.

Using an equation

Let q represent the number of quarters. Then the amount Bess has is ...

... 0.10(q -7) +0.25q = 2.80

... 0.35q - 0.70 = 2.80

... 0.35q = 3.50 . . . . . add 0.70 . . . . . . . this should look familiar

... q = 3.50/0.35 = 10

area = length x width

length = 2 x width

32 = 2 x width x width

32 = 2 x width^2

36 = width ^2  

width = 6

length = 12

area is 32

perimeter = 2 x 12 + 2 x 6 = 24 + 12 = 36

step-by-step explanation:

1,918

step-by-step explanation: