Question

А) (-5/8+7/9)*7.2 б) 14*(2 1/14-5/7)

Answer 1

Ответ:

Надеюсь помогла!

Пошаговое объяснение:

-5/8+7/9=9/72

9/72*7,2= 9/10

21/14-5/7= 11/14

14*11/14=11/1=11

Answer 2

Ответ:

а) 11/10= 1,1

б) -3 22/35*14= -5,8

Answer 3

Let's solve these expressions step by step:

а) $(-5/8 + 7/9) \times 7.2$

To solve this, first find the common denominator for $-5/8$ and $7/9$, which is $8 \times 9 = 72$.

$(-5/8 + 7/9) \times 7.2 = \left(-\frac{45}{72} + \frac{56}{72}\right) \times 7.2$

Now, add the fractions:

$\frac{-45 + 56}{72} \times 7.2 = \frac{11}{72} \times 7.2$

Multiply the fraction by $7.2$:

$\frac{11 \times 7.2}{72} = \frac{79.2}{72} = 1.1$

So, the result of $(-5/8 + 7/9) \times 7.2$ is approximately $1.1$.

b) $14 \times \left(2 \frac{1}{14} - \frac{5}{7}\right)$

First, convert the mixed number $2 \frac{1}{14}$ to an improper fraction:

$2 \frac{1}{14} = \frac{2 \times 14 + 1}{14} = \frac{29}{14}$

Now the expression becomes:

$14 \times \left(\frac{29}{14} - \frac{5}{7}\right)$

Find a common denominator, which is $14$:

$14 \times \left(\frac{29}{14} - \frac{10}{14}\right)$

Subtract the fractions:

$14 \times \frac{19}{14} = \frac{19 \times 14}{14} = 19$

So, the result of $14 \times \left(2 \frac{1}{14} - \frac{5}{7}\right)$ is $19$.