Question

(13/19 - 15/38)× 9 1/2 = найдите значения выражения 4 × 1 1/2 + 1 23/25 : 3/20 =(6 2/7 - 3 1/3 + 1 1/9 -2 20/21)× 2 13/25 =

Answer 1

Ответ:

(13/19 - 15/38)× 9 1/2 = 13,1710526316

4 × 1 1/2 + 1 23/25 : 3/20 = 22,082

(6 2/7 - 3 1/3 + 1 1/9 -2 20/21)× 2 13/25 = −91,420952381

Пошаговое объяснение:

Answer 2

To solve these expressions, we need to follow the order of operations (PEMDAS) which is Parentheses, Exponents, Multiplication and Division (from left to right), and Addition and Subtraction (from left to right). We also need to simplify any fractions before performing any operations.

1. (13/19 - 15/38)× 9 1/2:

To subtract fractions with different denominators, we need to find a common denominator first. The common denominator for 19 and 38 is 722. So we have:

(13/19 - 15/38) = (13×38/722 - 15×19/722) = (494/722 - 285/722) = -191/722

Now we can substitute this value into the expression:

(-191/722) × 9 1/2

We can convert the mixed number 9 1/2 to an improper fraction by multiplying the whole number by the denominator and adding the numerator. We have:

9 1/2 = (9×2 + 1)/2 = 19/2

Substituting this value, we have:

(-191/722) × 19/2 = -18109/1444

So the value of the expression is -18109/1444.

2. 4 × 1 1/2 + 1 23/25 : 3/20:

We need to simplify the fraction 1 1/2 to an improper fraction:

1 1/2 = (1×2 + 1)/2 = 3/2

Substituting this value, we have:

4 × 3/2 + 1 23/25 : 3/20

We need to perform the division first. To divide by a fraction, we can multiply by its reciprocal. The reciprocal of 3/20 is 20/3, so we have:

1 23/25 : 3/20 = 1 23/25 × 20/3 = (1×25 + 23)/25 × 20/3 = 1160/75

Substituting this value, we have:

4 × 3/2 + 1160/75

We need to find a common denominator to add these fractions. The common denominator for 2 and 75 is 150, so we have:

4 × 3/2 + 1160/75 = (4×3×75/150) + (1160/75) = (900/150) + (1160/75) = 12/2 + 232/15

Now we can add the fractions:

12/2 + 232/15 = 6 + 15 7/15

So the value of the expression is 15 7/15.

3. (6 2/7 - 3 1/3 + 1 1/9 -2 20/21)× 2 13/25:

We need to simplify all the mixed numbers to improper fractions:

6 2/7 = (6×7 + 2)/7 = 44/7

3 1/3 = (3×3 + 1)/3 = 10/3

1 1/9 = (1×9 + 1)/9 = 10/9

2 20/21 = (2×21 + 20)/21 = 62/21

Substituting these values, we have:

(44/7 - 10/3 + 10/9 - 62/21) × 2 13/25

We need to find a common denominator for the