Question

(5целых1/4-4целых21/40):1целую9/20

Answer 1

Ответ:

-4-(4 целых 21/40-5,25) : 1 целых 9/20=-2  7/19

1)4  21/40-5,25=4,525-5,25=-0,725

2)  -0,725 : 1 9/20=-0,725:0,95=-725/95=-145/19=-1  12/19

3)-4-(-1 12/19)=-4+1 12/19=-2  7/19

Answer 2

To solve the expression (5 1/4 - 4 21/40) ÷ 1 9/20, we need to convert all the mixed numbers into improper fractions and perform the subtraction and division.

First, let's convert the mixed numbers into improper fractions: 5 1/4 = (5 * 4 + 1) / 4 = 21/4 4 21/40 = (4 * 40 + 21) / 40 = 181/40 1 9/20 = (1 * 20 + 9) / 20 = 29/20

Now let's substitute these values into the expression: (21/4 - 181/40) ÷ 29/20

To subtract fractions, we need a common denominator. The least common multiple of 4 and 40 is 40, so we'll convert both fractions: 21/4 = (21 * 10) / (4 * 10) = 210/40 181/40 remains as is.

Substituting the values again: (210/40 - 181/40) ÷ 29/20

Now we can subtract the fractions: (210/40 - 181/40) = (210 - 181) / 40 = 29/40

Substituting the new value: (29/40) ÷ 29/20

To divide fractions, we multiply the first fraction by the reciprocal of the second fraction: (29/40) * (20/29) = (29 * 20) / (40 * 29) = 580/1160

Simplifying the fraction by dividing both the numerator and denominator by their greatest common divisor (GCD): GCD(580, 1160) = 580 580/580 = 1

Therefore, the result of the expression (5 1/4 - 4 21/40) ÷ 1 9/20 is 1.