Question

14-13,2:(3 11/21-2 4/5)

Answer 1

1. 3 11/21 - 2 4/5 = 1 55 - 84/105 = 105+55-84/105 = 76/105
2. 14 - 13,2 = 0,8
3. 0,8 : 76/105 = 8/10 * 105/76 (сократим 8 и 76 на 4, и 10 и 105 на 5) = 2/2 * 21/19 (сокращаем 2 и 2) = 1 2/19

Answer 2

To calculate the expression "14-13,2:(3 11/21-2 4/5)", we need to break it down step by step.

Let's start with the subtraction inside the parentheses: (3 11/21 - 2 4/5).

To perform this operation, we need to convert the mixed numbers into improper fractions.

3 11/21 = (3 * 21 + 11) / 21 = 64/21

2 4/5 = (2 * 5 + 4) / 5 = 14/5

Now we can subtract the fractions:

64/21 - 14/5

To subtract fractions, we need to have a common denominator. The least common multiple of 21 and 5 is 105.

Converting the fractions to have a common denominator:

(64/21) * (5/5) = 320/105 (14/5) * (21/21) = 294/105

Now we can subtract the fractions:

320/105 - 294/105 = (320 - 294) / 105 = 26/105

Next, we have the division operation: 14 - 13,2 ÷ (26/105).

To divide by a fraction, we invert the fraction and multiply:

13,2 ÷ (26/105) = 13,2 * (105/26)

To multiply mixed numbers, we first convert them to improper fractions:

13,2 = (13 * 10 + 2) / 10 = 132/10 = 66/5

Now we can multiply the fractions:

66/5 * (105/26)

Canceling out common factors:

(66/1) * (21/26) = 66 * 21 / (1 * 26) = 1386/26 = 693/13

Finally, we can perform the subtraction:

14 - 693/13

To subtract a fraction from a whole number, we need to convert the whole number into a fraction with the same denominator:

14 = 14/1

Now we can subtract the fractions:

14/1 - 693/13

To subtract fractions, we need a common denominator. The least common multiple of 1 and 13 is 13.

Converting the fractions to have a common denominator:

(14/1) * (13/13) = 182/13

Now we can subtract the fractions:

182/13 - 693/13 = (182 - 693) / 13 = -511/13

Therefore, the value of the expression "14-13,2:(3 11/21-2 4/5)" is -511/13.