Kevin and randy muise have a jar containing 69 coins, all of which are either quarters or nickels. The total value of the coins in the jar is $13.05 how many of each type of coin do they have ?

just sum

10 + 10 = 20

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15

139 divided by a number

step-by-step explanation: