Question

9 - 3 1/2 × ( 1 3/7 + 2 1/2 ) ÷ 2 1/7​

Answer 1

1) 1 3/7 + 2 1/2 = 1 6/14 + 2 7/14 = 3 13/14.
2) 3 1/2 • 3 13/14 = 7/2 • 55/14 = 55/4.
3) 55/4 : 2 1/7 = 55/4 : 15/7 = 55/4 • 7/15 = 77/12 = 6 5/12.
4) 9 - 6 5/12 = 8 12/12 - 6 5/12 = 2 7/12.
Ответ: 2 7/12

Answer 2

To solve the given expression, let's break it down step by step.

Step 1: Simplify the addition inside the parentheses: 1 3/7 + 2 1/2

To add fractions, we need to find a common denominator. The common denominator here is 14.

1 3/7 = (7/7 * 1) + 3/7 = 7/7 + 3/7 = 10/7 2 1/2 = (2/2 * 1) + 1/2 = 2/2 + 1/2 = 3/2

Now, let's add the fractions: 10/7 + 3/2

To add fractions, we need a common denominator. The common denominator here is 14.

10/7 = (2/2 * 5) / 7 = 10/14 3/2 = (7/7 * 3) / 2 = 21/14

Now, we can add the fractions: 10/14 + 21/14 = 31/14

Step 2: Multiply the result from step 1 with 3 1/2: 31/14 * 3 1/2

To multiply a whole number by a fraction, we convert the whole number to a fraction by putting it over 1:

3 1/2 = (2/2 * 3) + 1/2 = 6/2 + 1/2 = 7/2

Now, we can multiply the fractions: 31/14 * 7/2

To multiply fractions, we multiply the numerators and denominators separately: (31 * 7) / (14 * 2) = 217/28

Step 3: Divide the result from step 2 by 2 1/7: 217/28 ÷ 2 1/7

To divide by a mixed number, we convert the mixed number to an improper fraction:

2 1/7 = (7/7 * 2) + 1/7 = 14/7 + 1/7 = 15/7

Now, we can divide the fractions: (217/28) / (15/7)

To divide fractions, we multiply by the reciprocal of the divisor: (217/28) * (7/15)

Now, we can multiply the fractions: (217 * 7) / (28 * 15) = 1519/420

Therefore, the final result of the expression 9 - 3 1/2 × (1 3/7 + 2 1/2) ÷ 2 1/7 is 1519/420.