Question

( 20 8\15 * 7 1\2 - 54 3\5 *2\5) : ( 3 13\21*8 2\5 - 29 2\5) - 5\6 * 1 1\5 + 21\25

Answer 1

Я решила, думаю ты поймешь мой почерк)

Answer 2

To solve this expression step by step, we'll follow the order of operations (PEMDAS/BODMAS - Parentheses/Brackets, Exponents/Orders, Multiplication and Division, Addition and Subtraction):

1. Start by simplifying each part of the expression separately:

   • $20 \frac{8}{15} \cdot 7 \frac{1}{2} = 20 \cdot \frac{8}{15} \cdot 7 \cdot \frac{1}{2}$
   • $54 \frac{3}{5} \cdot \frac{2}{5} = 54 \cdot \frac{3}{5} \cdot \frac{2}{5}$
   • $3 \frac{13}{21} \cdot 8 \frac{2}{5} = 3 \cdot \frac{13}{21} \cdot 8 \cdot \frac{2}{5}$
   • $29 \frac{2}{5} = 29 \cdot \frac{2}{5}$
   • $5 \frac{1}{6} \cdot 1 \frac{1}{5} = 5 \cdot \frac{1}{6} \cdot 1 \cdot \frac{1}{5}$
   • $21 \frac{25}{25} = 21$

2. Perform the multiplications within each part:

   • $20 \cdot \frac{8}{15} \cdot 7 \cdot \frac{1}{2} = \frac{20 \cdot 8 \cdot 7 \cdot 1}{15 \cdot 2} = \frac{1120}{30}$
   • $54 \cdot \frac{3}{5} \cdot \frac{2}{5} = \frac{54 \cdot 3 \cdot 2}{5 \cdot 5} = \frac{324}{25}$
   • $3 \cdot \frac{13}{21} \cdot 8 \cdot \frac{2}{5} = \frac{3 \cdot 13 \cdot 8 \cdot 2}{21 \cdot 5} = \frac{624}{35}$
   • $29 \cdot \frac{2}{5} = \frac{29 \cdot 2}{5} = \frac{58}{5}$
   • $5 \cdot \frac{1}{6} \cdot 1 \cdot \frac{1}{5} = \frac{5 \cdot 1 \cdot 1 \cdot 1}{6 \cdot 5} = \frac{5}{30}$

3. Now, we can rewrite the expression with the simplified values:

   $\frac{\frac{1120}{30} - \frac{324}{25}}{\frac{624}{35} - \frac{58}{5}} - \frac{5}{30} + 21$

4. Continue to simplify:

   $\frac{\frac{1120}{30} - \frac{324}{25}}{\frac{624}{35} - \frac{58}{5}} - \frac{5}{30} + 21$