Question

3a+b/2c-b при а=2/7, b=0,25 и c=19/28

Answer 1

Ответ:1. Смотри фото

Answer 2

To evaluate the expression 3a+b/2c-b with a=2/7, b=0.25, and c=19/28, we can substitute the given values into the expression and perform the necessary calculations step by step.

Let's start with the substitutions:

a = 2/7 b = 0.25 c = 19/28

Now we can substitute these values into the expression:

3a + b / (2c - b)

Replacing the variables with their respective values:

3(2/7) + 0.25 / (2(19/28) - 0.25)

Next, simplify the expression:

6/7 + 0.25 / (38/28 - 0.25)

To simplify further, we need to find a common denominator for the fractions:

6/7 + 0.25 / ((38/28) - (7/28))

The common denominator for the fractions is 28:

6/7 + 0.25 / (31/28)

Now, we can add the fractions:

(6/7) + (0.25 * 28) / 31

Multiplying the numerator of the second fraction:

6/7 + 7/31

To add the fractions, we need a common denominator, which is 7 * 31 = 217:

(6 * 31) / (7 * 31) + (7 * 7) / (31 * 7)

186/217 + 49/217

Now that the fractions have a common denominator, we can add the numerators:

(186 + 49) / 217

235/217

Therefore, the value of the expression 3a + b / (2c - b) when a=2/7, b=0.25, and c=19/28 is 235/217.