Question

А) - 5/7 + 3/14 = б)3/8 * (- 4/9) = 2/3: (- 7/9) = 23/11 - 19/22 = - 3 1/3 * 0,9 = 0,27 : 0,9 = 4/9 - 5/18 = - 21/5 * 10/11 = - 0,26 : (- 0,13) = 0,5 -3,1 = - 15/12 * 1/17 = - 1/3 : 0,6 = 35 БАЛОВ аааа #$

Answer 1

Ответ:

все на фотфотоя надеюсь что все понятно

Answer 2

To solve the given expressions, let's go step by step:

a) - 5/7 + 3/14:

To add fractions with different denominators, we need to find a common denominator. In this case, the common denominator is 14:

• 5/7 + 3/14 = - 10/14 + 3/14

Now we can add the fractions:

• 10/14 + 3/14 = - 7/14

Simplifying the fraction:

• 7/14 = - 1/2

b) 3/8 * (- 4/9):

To multiply fractions, we multiply the numerators together and the denominators together:

3/8 * (- 4/9) = (3 * -4)/(8 * 9) = -12/72

Simplifying the fraction:

-12/72 = -1/6

c) 2/3 : (- 7/9):

Dividing by a fraction is the same as multiplying by its reciprocal:

2/3 : (- 7/9) = 2/3 * (-9/7)

Now we can multiply the fractions:

2/3 * (-9/7) = (2 * -9)/(3 * 7) = -18/21

Simplifying the fraction:

-18/21 = -6/7

d) 23/11 - 19/22:

To subtract fractions with different denominators, we need to find a common denominator. In this case, the common denominator is 22:

23/11 - 19/22 = (2 * 23)/ (2 * 11) - 19/22 = 46/22 - 19/22

Now we can subtract the fractions:

46/22 - 19/22 = 27/22

e) - 3 1/3 * 0.9:

To multiply a mixed number by a decimal, we first convert the mixed number to an improper fraction:

• 3 1/3 = - 10/3

Now we can multiply:

• 10/3 * 0.9 = - (10 * 0.9)/3 = - 9/3 = - 3

f) 0.27 : 0.9:

To divide decimals, we move the decimal point of the divisor (0.9) one place to the right and then perform the division:

0.27 : 0.9 = 0.27 / 0.9 = 0.27 * 10/9 = (0.27 * 10)/(0.9 * 1) = 2.7/0.9

Now we can simplify the fraction by multiplying the numerator and denominator by 10:

2.7/0.9 = (2.7 * 10)/(0.9 * 10) = 27/9 = 3

g) 4/9 - 5/18:

To subtract fractions with different denominators, we need to find a common denominator. In this case, the common denominator is 18:

4/9 - 5/18 = (2 * 4)/(2 * 9) - 5/18 = 8/18 - 5/18

Now we can subtract the fractions:

8/18 - 5/18 = 3/18

Simplifying the fraction:

3/18 = 1/6

h) - 21/5 * 10/11:

To multiply fractions, we multiply the numerators together and the denominators together:

• 21/5 * 10/11 = (21 * 10)/(5 * 11) = 210/55

Simplifying the fraction:

210/55 = 42/11

i) - 0.26 : (- 0.13):

To divide decimals, we move the decimal point of the divisor (- 0.13) one place to the right and then perform the division:

• 0.26 : (- 0.13) = - 0.26 / (- 0.13) = 0.26 / 0.13 = 2

j) 0.5 - 3.1:

To subtract decimals, we simply subtract the numbers:

0.5 - 3.1 = - 2.6

k) - 15/12 * 1/17:

To multiply fractions, we multiply the numerators together and the denominators together:

• 15/12 * 1/17 = (15 * 1)/(12 * 17) = 15/204

Simplifying the fraction:

15/204 cannot be simplified further.

l) - 1/3 : 0.6:

To divide a fraction by a decimal, we multiply the fraction by the reciprocal of the decimal:

• 1/3 : 0.6 = - 1/3 * (1/0.6)

Now we can multiply the fractions:

• 1/3 * (1/0.6) = - 1/(3 * 0.6) = - 1/1.8

To express the fraction with a decimal denominator, we can multiply both the numerator and denominator by 10:

• 1/1.8 = - 10/18

Simplifying the fraction:

• 10/18 = - 5/9

Adding up the scores, we have:

a) -1/2 = 0.5 b) -1/6 = 0.17 c) -6/7 = -0.86 d) 27/22 = 1.23 e) -3 f) 3 g) 1/6 = 0.17 h) 42/11 ≈ 3.82 i) 2 j) -2.6 k) 15/204 ≈ 0.073 l) -5/9 ≈ -0.56

Adding up the approximate scores, we get 0.5 + 0.17 + (-0.86) + 1.23 + (-3) + 3 + 0.17 + 3.82 + 2 + (-2.6) + 0.073 + (-0.56) ≈ 5.12

Therefore, the total score is approximately 5.12 points.