Question 259739
1. Let Grandmother's age = X

The Equation: {{{X /5 = 15}}}
Multiply both sides by 5
{{{5 * X / 5 = 15 * 5}}}
Simplify the equation
{{{highlight(X = 75)}}}

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2. Total cost = $390
She is making 12 payments

The equation
{{{X = $390 / 12}}}
{{{highlight(X = 32.5)}}}
She is paying $32.5 each time