Question

Найдите значение выражения (5 2/9y + 3 1/3) x 3 - 7 2/3y
Если y=3 1/8
и если y=1.4

Answer 1

(5 2/9y + 3 1/3) * 3 - 7 2/3y = (47/9y + 10/3) * 3 - 23/3y= (47/3 *y + 10) - 23/3y;
если у= 3 1/8 = 25/8 то (47/3 *y + 10) - 23/3y = (47/3 *25/8 + 10) - 23/3*25/8 =(47*25+10*3*8 - 23*25)/(3*8) = 840/24=35;
если у= 1,4 = 7/5 то (47/3 *y + 10) - 23/3y = (47/3 *7/5 + 10) - 23/3*7/5 = (47*7 + 10*3*5 - 23*7)/(5*3)=318/15=106/5= 21 1/5;

Answer 2

5 2/9y *3 +3 1/3*3- 7 2/3y=15 2/3y- 7 2/3y+10=8y+10
8*3 1/8 +10=25+10=35
8*1,4+10=11,2+10=21,2