Question

the cost of mathematics books is Rs 25\3by4 and that of science books is Rs 20\1by 2 . which costs more and by how much

Answer 1

$maths = 25 \times \frac{3}{4} = \frac{103}{4} = 25.75$

$science = 20 \times \frac{1}{2} = \frac{41}{2} = 20.5$

clearly, maths book costs more.

$diff. =25.75 - 20.5 = 5.25$