Answer:
She will need to work 24 hours to buy a bike
Step-by-step explanation:
Cost of bike = $530
When her mum gives her $170,
Remaining money for the bike = $530 - $170
= $360
If she earns $15 in 1hr,
She will earn $360 in => [tex]\frac{360}{15} hours[/tex]
= 24 hours
∴She will need to work 24hrs to buy the bike
Hope this helps :)