(у+20+18+30+36+24)/6=28

<span>(у+20+18+30+36+24)/6=28</span>

<span>у+20+18+30+36+24 = 28*6</span>

<span>у+128 = 168</span>

<span>у = 168-128</span>

<span>у = 40</span>

<span>Ответ: у = 40</span>

<span>
</span>

 (у+128):6=28
у+128=28*6
у+128=168
у=168-128
у=40