Question

20,8-(7 19/20-8 3/5) ​

Answer 1

Ответ:

Пошаговое объяснение:

20,8-(7¹⁹/₂₀-8³/₅)=20,8-(7,95-8,6)=20,8-(-0,65)=20,8+0,65=21,45.

Answer 2

To solve the expression 20.8 - (7 19/20 - 8 3/5), we need to simplify the mixed numbers within the parentheses first and then perform the subtraction.

Let's simplify the mixed numbers: 7 19/20 = (7 * 20 + 19) / 20 = 159/20 8 3/5 = (8 * 5 + 3) / 5 = 43/5

Now, we can rewrite the expression: 20.8 - (159/20 - 43/5)

To subtract fractions, we need a common denominator. The least common multiple (LCM) of 20 and 5 is 20, so we can convert both fractions:

159/20 = (159 * 1) / (20 * 1) = 159/20 43/5 = (43 * 4) / (5 * 4) = 172/20

Now, we can rewrite the expression again: 20.8 - (159/20 - 172/20)

To subtract the fractions, we subtract their numerators while keeping the common denominator: 159/20 - 172/20 = (159 - 172) / 20 = -13/20

Substituting back into the expression: 20.8 - (-13/20)

When subtracting a fraction, we can rewrite it as addition with the negative: 20.8 + 13/20

Now, we need a common denominator to perform addition: 20.8 = (20 * 20 + 8) / 20 = 416/20

416/20 + 13/20 = (416 + 13) / 20 = 429/20

Therefore, the simplified value of the expression 20.8 - (7 19/20 - 8 3/5) is 429/20.