Answer :
Answer:
The rate of exchange is 8%
Step-by-step explanation:
Given as :
Shelley delivered 12 newspaper after 20 min
And She delivered 36 papers after 60 min
Let the exchange rate = R %
So,
Final value = Initial value × ( 1 + [tex]\frac{Rate}{100}[/tex] )
Or, 36 × 60 = 12 × 20 × ( 1 + [tex]\frac{Rate}{100}[/tex] )
Or, 2160 = 240 × ( 1 + [tex]\frac{Rate}{100}[/tex] )
Or, [tex]\frac{2160}{240}[/tex] = ( 1 + [tex]\frac{Rate}{100}[/tex] )
Or, 9 = ( 1 + [tex]\frac{Rate}{100}[/tex] )
∴ [tex]\frac{Rate}{100}[/tex] = 9 -1 = 8
Or , Rate = 8%
Hence The rate of exchange is 8% Answer