Question

2 5/6-1 5/12=? 3 2/7-6/7=? 3 1/4*2/5=? 20:2 1/2=?

Answer 1

Ответ:

Пошаговое объяснение:

2 5/6-1 5/12=2 10/12-1 5/12=1 5/12

3 2/7-6/7=2 3/7

3 1/4*2/5=13/4*2/5=13/10=1 3/10

20:2 1/2=20*2/5=8

Answer 2

Let's solve these mathematical expressions step by step:

1. $2 \frac{5}{6} - 1 \frac{5}{12}$: First, subtract the whole numbers: $2 - 1 = 1$. Now, subtract the fractions: $\frac{5}{6} - \frac{5}{12}$. To subtract these fractions, you need to find a common denominator. In this case, the common denominator is 12. So, rewrite both fractions with the common denominator: $\frac{10}{12} - \frac{5}{12}$. Now, subtract the numerators: $\frac{10 - 5}{12} = \frac{5}{12}$. Combine the whole number and fraction: $1 \frac{5}{12}$.

2. $3 \frac{2}{7} - \frac{6}{7}$: First, subtract the whole numbers: $3 - 0 = 3$. Now, subtract the fractions: $\frac{2}{7} - \frac{6}{7}$. Since the denominators are the same, you can directly subtract the numerators: $\frac{2 - 6}{7} = \frac{-4}{7}$.

3. $3 \frac{1}{4} \times \frac{2}{5}$: To multiply mixed numbers, you can first convert them to improper fractions. To do this for $3 \frac{1}{4}$, multiply the whole number (3) by the denominator (4) and add the numerator (1): $3 \frac{1}{4} = \frac{3 \cdot 4 + 1}{4} = \frac{12 + 1}{4} = \frac{13}{4}$. Now, multiply the improper fraction with the other fraction: $\frac{13}{4} \times \frac{2}{5} = \frac{13 \cdot 2}{4 \cdot 5} = \frac{26}{20}$. To simplify, divide both the numerator and denominator by their greatest common divisor, which is 2: $\frac{26/2}{20/2} = \frac{13}{10}$.

4. $20 \div 2 \frac{1}{2}$: To divide by a mixed number, first convert it to an improper fraction. To do this for $2 \frac{1}{2}$, multiply the whole number (2) by the denominator (2) and add the numerator (1): $2 \frac{1}{2} = \frac{2 \cdot 2 + 1}{2} = \frac{4 + 1}{2} = \frac{5}{2}$. Now, divide 20 by this improper fraction: $20 \div \frac{5}{2} = 20 \cdot \frac{2}{5} = \frac{40}{5}$. To simplify, divide both the numerator and denominator by their greatest common divisor, which is 5: $\frac{40/5}{5/5} = \frac{8}{1} = 8$.

So, the solutions are:

1. $2 \frac{5}{6} - 1 \frac{5}{12} = 1 \frac{5}{12}$
2. $3 \frac{2}{7} - \frac{6}{7} = \frac{-4}{7}$