Question

1 1/2*2 2/3 г) 2 1/7 *1 13/15 д) 2/3÷2 е) 10÷2 1/2 ж) 18÷7 1/5 з) 6/7÷3

Answer 1

1 1/2 · 2 2/3 = 3/2 · 8/3 = 8/2 = 4

г) 2 1/7 · 1 13/15 = 15/7 · 28/15 = 28/7 = 4

д) 2/3 : 2 = 2/3 · 1/2 = 1/3

е) 10 : 2 1/2 = 10 : 5/2 = 10 · 2/5 = 20/5 = 4

ж) 18 : 7 1/5 = 18 : 36/5 = 18/1 · 5/36 = (1·5)/(1·2) = 5/2 = 2 1/2

з) 6/7 : 3 = 6/7 · 1/3 = (2·1)/(7·1) = 2/7

Answer 2

Объяснение:

$\tt\displaystyle 1\frac{1}{2}*2\frac{2}{3}=\frac{3}{2}*\frac{8}{3}=\frac{8}{2}=4 \\\\ 2\frac{1}{7}*1\frac{{13}}{{15}}=\frac{{15}}{7}*\frac{{28}}{{15}}=\frac{{28}}{7}=4 \\\\ \frac{2}{3}:2=\frac{2}{3}*\frac{1}{2}=\frac{1}{3} \\\\ 10:2\frac{1}{2}=10:\frac{5}{2}=10*\frac{2}{5}=\frac{{10*2}}{5}=2*2=4 \\\\ 18:7\frac{1}{5}=18:\frac{{36}}{5}=18*\frac{5}{{36}}=\frac{{18*5}}{{36}}=\frac{5}{2}=2\frac{1}{2}\\\\\frac{6}{7}:3=\frac{6}{7}*\frac{1}{3}=\frac{2}{7}$

Answer 3

To simplify the given expressions, let's perform the calculations step by step:

a) 1 1/2 * 2 2/3: To multiply mixed numbers, we first convert them to improper fractions. 1 1/2 = (2 * 1 + 1)/2 = 3/2 2 2/3 = (3 * 2 + 2)/3 = 8/3

Now, multiply the fractions: (3/2) * (8/3) = (3 * 8)/(2 * 3) = 24/6

Simplifying the fraction, we get: 24/6 = 4/1 = 4

Therefore, 1 1/2 * 2 2/3 is equal to 4.

b) 2 1/7 * 1 13/15: Following the same process as before: 2 1/7 = (7 * 2 + 1)/7 = 15/7 1 13/15 = (15 * 1 + 13)/15 = 28/15

Now, multiply the fractions: (15/7) * (28/15) = (15 * 28)/(7 * 15) = 420/105

Simplifying the fraction, we get: 420/105 = 4/1 = 4

Therefore, 2 1/7 * 1 13/15 is also equal to 4.

c) 2/3 ÷ 2: To divide fractions, we multiply the first fraction by the reciprocal of the second fraction. Reciprocal of 2 is 1/2.

Therefore, (2/3) ÷ 2 = (2/3) * (1/2) = 2/6

Simplifying the fraction, we get: 2/6 = 1/3

Therefore, 2/3 ÷ 2 is equal to 1/3.

d) 10 ÷ 2 1/2: First, convert the mixed number to an improper fraction. 2 1/2 = (2 * 2 + 1)/2 = 5/2

Now, divide 10 by 5/2: 10 ÷ (5/2) = 10 * (2/5) = 20/5

Simplifying the fraction, we get: 20/5 = 4/1 = 4

Therefore, 10 ÷ 2 1/2 is equal to 4.

e) 18 ÷ 7 1/5: Again, convert the mixed number to an improper fraction. 7 1/5 = (5 * 7 + 1)/5 = 36/5

Now, divide 18 by 36/5: 18 ÷ (36/5) = 18 * (5/36) = 90/36

Simplifying the fraction, we get: 90/36 = 5/2

Therefore, 18 ÷ 7 1/5 is equal to 5/2.

f) 6/7 ÷ 3: To divide fractions, multiply the first fraction by the reciprocal of the second fraction. Reciprocal of 3 is 1/3.

Therefore, (6/7) ÷ 3 = (6/7) * (1/3) = 6/21

Simplifying the fraction, we get: 6/21 = 2/7

Therefore, 6/7 ÷ 3 is equal to 2/7.