If you would like to know how much weeks would it take to earn $5000, you can calculate this using the following steps:
$700 ... 4 weeks
$5000 ... x weeks = ?
700 * x = 4 * 5000 /700
x = 4 * 5000 / 700
x = 28.57
x = 29 weeks
The correct result would be 29 weeks.