Question

Вычесли рациональным способом.1. (0,9×5+5×0,6)-(0,7×2+3×0,7)

Answer 1

5(0,9+0,6)-0,7(2+3)=5*1,5-0,7*5=7,5-3,5=4

Answer 2

1) 0,9 • 5 • 0,6 = 5 • ( 0,9 + 0,6 ) = 5 • 1,5
2) 0,7 • 2 + 3 • 0,7 = 0,7 • ( 2 + 3 ) = 0,7 • 5
3) 5 • 1,5 - 0,7 • 5 = 5 • ( 1,5 - 0,7 ) = 5 • 0,8 = 4
Ответ 4

Answer 3

To solve the expression (0.9 × 5 + 5 × 0.6) - (0.7 × 2 + 3 × 0.7) rationally, we can follow the order of operations, also known as PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction).

Let's break down the steps:

Step 1: Evaluate the expressions within parentheses

(0.9 × 5 + 5 × 0.6) - (0.7 × 2 + 3 × 0.7)

First, we can multiply within each set of parentheses:

(0.9 × 5 + 5 × 0.6) - (0.7 × 2 + 3 × 0.7) (4.5 + 3) - (1.4 + 2.1)

Step 2: Perform addition and subtraction from left to right

Now, we can add and subtract within each set of parentheses:

(4.5 + 3) - (1.4 + 2.1) 7.5 - 3.5

Step 3: Perform the final subtraction

Finally, we can subtract the two results:

7.5 - 3.5 = 4

Therefore, the result of the expression (0.9 × 5 + 5 × 0.6) - (0.7 × 2 + 3 × 0.7) is 4.