I’m guessing that this is for systems of equations?
n - nickels
d - dimes
These are the equations you start off with.
n = 5d-2
0.95 = 0.10d+0.05n
Substitute the top equation for n into the variable n in the bottom equation.
0.95 = 0.10d+0.05(5d-2)
Solve for d.
0.95 = 0.10d+0.25d-0.10
1.05 = 0.35d
3 = d
Substitute d into the top equation and solve for n.
n = 5(3)-2
n = 15-3
n = 12
There are 3 dimes and 12 nickels in the coin purse! Hope this helped <3
10 x 25 = 250, well 20 x 25 is just double that, its 10 doubled x 25 so he probably just added it up. repeated addition really helps with times tables.
I think it is 9 1/2 feet.