Question

Starting on Sunday, each day Sania cycled twice as far as the day before for a whole week. If she cycled 3⁄4 km on Sunday, on which day did she first cycle over 15 km?

Answer 1

On Friday, she will cycle 24 km

Explanation:

So you're given that on Sunday, she rides 3/4 or .75 km and also that it doubles everyday.

A really easy way of doing this is to just go through it, like monday she goes 1.5 km, tuesday she goes 3km, wednesday she goes 6km, thursday she goes 12 km, and friday she goes 24 km (the first time she goes over 15km)