Let's call the original amount of money x.
We know that she has 2/5 of the original amount left, and that this is equal to $15.
Therefore, 2/5(x) = 15, and x = $37.50.
You flip the sign from > to < only when you are dividing by a negative number and in this case it would be negative 9.
Answer:
Step-by-step explanation:
Sec B
1) 5p⁻³ = 8*5⁻²
p⁻³ = 2³*5⁻²/5
p⁻³ =2³*5⁻³ { 1/a^m = a^-m}
p⁻³ = 5⁻³ /2⁻³ {a^m = 1/a^-m}
p⁻³ = (5/2)⁻³
p= 5/2
2) 4x² = 81
x² = 81/4
x² = 9² /2²
x² =(9/2)²
x = 9/2
3) 9^x/3 =81
9^x/3 = 9^2
Comparing the powers, x/3 = 2
x = 2*3 =6
x = 6