Toán X x 1/4 + X x 1/5 + X x 2 = 19,2 GIÚP MIK nha 08/07/2021 By Reagan X x 1/4 + X x 1/5 + X x 2 = 19,2 GIÚP MIK nha
Đáp án: Giải thích các bước giải: `x× 1/4+ x× 1/5+ x× 2= 19,2` `x× (1/4+ 1/5+ 2)= 19,2` `x× (5/20+ 4/20+ 40/20)= 19,2` `x× 2,45= 19,2` `x= 19,2: 2,45` `x= 7,836734694` Trả lời
X x $\dfrac{1}{4}$ + X x $\dfrac{1}{5}$ + X x 2 = 19,2 ⇔ X x ( $\dfrac{1}{4}$ + $\dfrac{1}{5}$ + 2) = 19,2 ⇔ X x ( $\dfrac{5}{20}$ + $\dfrac{4}{20}$ + $\dfrac{40}{20}$ ) = $\dfrac{96}{5}$ ⇔ X x $\dfrac{49}{20}$ = $\dfrac{96}{5}$ ⇔ X = $\dfrac{96}{5}$ : $\dfrac{49}{20}$ ⇔ X = $\dfrac{96}{5}$ x $\dfrac{20}{49}$ ⇔ X = $\dfrac{384}{49}$ ≈ 7,8 Trả lời
Đáp án:
Giải thích các bước giải:
`x× 1/4+ x× 1/5+ x× 2= 19,2`
`x× (1/4+ 1/5+ 2)= 19,2`
`x× (5/20+ 4/20+ 40/20)= 19,2`
`x× 2,45= 19,2`
`x= 19,2: 2,45`
`x= 7,836734694`
X x $\dfrac{1}{4}$ + X x $\dfrac{1}{5}$ + X x 2 = 19,2
⇔ X x ( $\dfrac{1}{4}$ + $\dfrac{1}{5}$ + 2) = 19,2
⇔ X x ( $\dfrac{5}{20}$ + $\dfrac{4}{20}$ + $\dfrac{40}{20}$ ) = $\dfrac{96}{5}$
⇔ X x $\dfrac{49}{20}$ = $\dfrac{96}{5}$
⇔ X = $\dfrac{96}{5}$ : $\dfrac{49}{20}$
⇔ X = $\dfrac{96}{5}$ x $\dfrac{20}{49}$
⇔ X = $\dfrac{384}{49}$ ≈ 7,8