He went upstream 3 hours and downstream two. 4x3=12 6x2=12
He went 24 miles.
1 quarter note=2 eighth notes
1 eight note=2 sixteenth notes
so
1 quarter note=4 sixteenth note
so
times 3 both sides
3 quarter notes=12 sixteenth notes
Given that the number is x,
10% increase will give us a new number of:
110/100*x
=1.1x
10% decrease will give us a new number of:
90/100*1.1x
=0.99x
This implies the new number is less than the original number