Question

А) 22,5÷ 5 2/7-2 2/5 б) (7 1/4-6 7/18)×7,2+2 4/5

Answer 1

Ответ: А) 1,6 Б) 9

Пошаговое объяснение:

А) 22 2/10:5 2/7=222/10:37/7=222/10*7/37=6/10*7/1=42/10=4,2

4,2-2 3/5=42/10-13/5=42/10-26/10=16/10=1,6

Б)7 1/4-6 7/18=7-6+1/4-7/18=1+9/36-14/36=1+(-5/36)=36/36-5/36=31/36

31/36*7,2=31/36*72/10=31/1*2/10=62/10=6,2

6,2+2,8=9

Answer 2

Let's solve the expressions step by step:

а) 22.5 ÷ 5 2/7 - 2 2/5

Step 1: Convert the mixed numbers into improper fractions. 5 2/7 = (5 * 7 + 2) / 7 = 37 / 7 2 2/5 = (2 * 5 + 2) / 5 = 12 / 5

Step 2: Perform the division and subtraction operations. 22.5 ÷ 5 2/7 = 22.5 ÷ (37 / 7) = 22.5 * (7 / 37) = 2.837837837837838 (approximately) 2.837837837837838 - 2 2/5 = 2.837837837837838 - (12 / 5) = 2.837837837837838 - 2.4 = 0.437837837837838 (approximately)

So, the value of а) is approximately 0.4378.

б) (7 1/4 - 6 7/18) × 7.2 + 2 4/5

Step 1: Convert the mixed numbers into improper fractions. 7 1/4 = (7 * 4 + 1) / 4 = 29 / 4 6 7/18 = (6 * 18 + 7) / 18 = 115 / 18 2 4/5 = (2 * 5 + 4) / 5 = 14 / 5

Step 2: Perform the subtraction, multiplication, and addition operations. (29 / 4 - 115 / 18) × 7.2 = ((29 * 9 - 115 * 2) / (4 * 9)) × 7.2 = (261 - 230) / 36 × 7.2 = 31 / 36 × 7.2 = 6.0 (exactly)

6.0 + 2 4/5 = 6.0 + (14 / 5) = 6.0 + 2.8 = 8.8

So, the value of б) is 8.8.