Question

How much time will Alex need to walk to his school, which is 2 1 /4 miles away from his house, if he would walk with the speed of 3 3/4mph

Answer 1

`\bf \stackrel{distance}{d}=\stackrel{rate}{r}\cdot \stackrel{time}{t}\qquad \qquad 2(1)/(4)m=3(3)/(4)(m)/(hr)\cdot t\implies \cfrac{2(1)/(4)m}{3(3)/(4)(m)/(hr)}=t \\\\\\ \cfrac{(9)/(4)m}{(15)/(4)(m)/(hr)}=t\implies \cfrac{9\underline{m}}{4}\cdot \cfrac{4hr}{15\underline{m}}=t\implies \cfrac{9\cdot 4}{4\cdot 15}hr=t\implies \cfrac{3}{5}hr=t`

so, 36 minutes then.