Question

7x/3 + 2x/9 + 5x/15= 12​

Answer 1

Given:

• $\large{\sf{\dfrac{7x}{3}+\dfrac{2x}{9}+\dfrac{5x}{15}\:=\:12}}$

Solution:

$\large{\sf{\dfrac{7x}{3}+\dfrac{2x}{9}+\dfrac{5x}{15}\:=\:12}}$

[We know that LCM of 3,9,15 is 45]

$\implies\large{\sf{\dfrac{15(7x)+5(2x)+3(5x)}{45} \:=\:12}}$

$\implies\large{\sf{\dfrac{105x+10x+15x}{45}\:=\: 12}}$

$\implies\large{\sf{\dfrac{130x}{45}\:=\: 12}}$

$\implies\large{\sf{130x\:=\: 12 × 45}}$

$\implies\large{\sf{130x\:=\: 540}}$

$\implies\large{\sf{x\:=\:\dfrac{540}{130}}}$

$\implies\large{\sf{x\:=\: \dfrac{54}{13}}}$

$\implies\large{\sf{x\:=\:4\dfrac{2}{13}}}$

Therefore,

• $\large{\boxed{\sf{\green{x\:=\: 4\dfrac{2}{13}\: or\: 4.153}}}}$