Отыскать значения выражения 1*8/17 : (12/17 + 2*7/11)= ( 2 *

1 * 8/17 : (12/17 + 2 * 7/11) = 748/3145.

1). 2 * 7/11 = (2 * 7) / 11 = 14/11 = 1 3/11; 

2). 12/17 + 1 3/11 = 12/17 + 14/11 = (12 * 11) / (17 * 11) + (14 * 17) / (11 * 17) = 132/187 + 238/187 = (132 + 238) / 187 = 370/187 = 1 183/187; 

3). 1 * 8/17 = 8/17; 

4). 8/17 : 1 183/187 = 8/17 * 187/370 = 1496/6290 = 748/3145. 

(2 * 3/4 + 2 * 1/5) * 16 = 30,4. 

1). 2 * 3/4 = 6/4 = 1 2/4 = 1 1/2; 

2). 2 * 1/5 = 2/5; 

3). 1 1/2 + 2/5 = 3/2 + 2/5 = 15/10 + 4/10 = 19/10 = 1 9/10; 

4). 1 9/10 * 16 = 19/10 * 16 = (19 * 16) / 10 = 304/10 = 30,4.