Question

Sendo x = 7/5 - 4/15 + 3/4, escreva o número x na forma decimal.

Answer 1

x=7/5-4/15+3/4
x=1,4-0,26+0,75
x=1,14+0,75
x=1,89

Answer 2

Calculando o m.m.c entre 5, 15 e 4:

05, 15, 04 | 2
05, 15, 02 | 2
05, 15, 01 | 5
01, 03, 01 | 3
01, 01, 01

m.m.c: 2 . 2 . 5 . 3 = 60
_______________________

$x=\dfrac{7}{5}-\dfrac{4}{15}+\dfrac{3}{4}$

Multiplicando todos os membros por 60:

$60\cdot x=60\cdot\dfrac{7}{5}-60\cdot\dfrac{4}{15}+60\cdot\dfrac{3}{4}$

Simplificando:

$60\cdot x=12\cdot7-4\cdot4+15\cdot3\\60\cdot x=84-16+45\\60\cdot x=113\\\\\boxed{\boxed{x=\dfrac{113}{60}}}$

Forma decimal:

$\boxed{\boxed{x=1,88333...}}$