Question

If two amount of money are in the ratio of 8:3. If the second is $4.05 what is the value of the first amount

Answer 1

Answer

Let the first amount be y,

$\sf \dashrightarrow 8 : 3 = y : 4.05$

$\sf \dashrightarrow \dfrac{8}{3} = \dfrac{y}{4.05}$

Cross multiply the numbers.

$\sf \dashrightarrow 8 \times 4.05 = y \times 3$

$\sf \dashrightarrow 32.4 = y \times 3$

$\sf \dashrightarrow y \times 3 = 32.4$

$\sf \dashrightarrow y = \dfrac{32.4}{3}$

$\sf \dashrightarrow y = \dfrac{324}{30}$

$\sf \dashrightarrow y = 10.8$

Hence, the first amount is $10.8.

Verification

$\sf \dashrightarrow 8 : 3 = y : 4.05$

$\sf \dashrightarrow 8 : 3 = 10.8 : 4.05$

$\sf \dashrightarrow \dfrac{8}{3} = \dfrac{10.8}{4.05}$

$\sf \dashrightarrow \dfrac{8}{3} = \dfrac{1080}{405}$

$\sf \dashrightarrow \dfrac{8}{3} = \dfrac{8}{3}$

$\sf \dashrightarrow LHS = RHS$