3,4*(9х+0,8)-15,17=24,27
3,4*(9х+0,8)=24,27+15,17
<em>3,4*(9х+0,8)=39,44</em>
<em>9х+0,8=39,44:3,4</em>
<em>9х+0,8=11,6</em>
<em>9х=11,6-0,8</em>
<em>9х=10,8</em>
<em>х=10,8:9</em>
<em>х=1,2</em>
2 * (14/15 : 2/3) = 2 целых 4/5
<span>1) 14/15 : 2/3 = 14/15 * 3/2 = (7*1)/(5*1) = 7/5 </span>
2) 2 * 7/5 = 14/5 = 2 целых 4/5
12/11 : 3/4 * 11/24 = 2/3
1) 12/11 : 3/4 = 12/11 * 4/3 = (4*4)/(11*1) = 16/11
2) 16/11 * 11/24 = (2*1)/(1*3) = 2/3
<span>1/2 * 2/3 * 3/4 * 5/4 = (1*2*3*5)/(2*3*4*4) = (1*5)/(4*4) = 5/16</span>
3) 20*11/14=16человек на двух инструментах играют
6\х\=4,2
\х\=0,7
х=0,7 х=-0,7