Question:
Tick (✓) the correct answer:
Four-fifths of a number is greater than three-fourths of the number by 4. The number is
(a) 12
(b) 64
(c) 80
(d) 102
Solution:
(c) 80
Let the number be $\mathrm{x}$.
$\therefore \frac{4}{5} x=\frac{3}{4} x+4$
$\Rightarrow \frac{4 x}{5}=\frac{3 x+16}{4}$
$\Rightarrow 16 x=15 x+80$
$\Rightarrow 16 x-15 x=80$
$\Rightarrow x=80$