Question

Rolf spent 15 hours last week practicing his saxophone if 3/10 of the time was spent practicing warm up routines, how much time did he spend practicing warm up routines ?

Answer 1

3/10 of the time = time spent on practicing warm up routines...
Time spent = 15 hours
remember that 'of' is usually multiply (x)
so ---- 3/10 x 15 =4.5 hrs

Hope this helps