Convert to find the equivalent rate

The nature park has a pride of 5 adult lions and 3 cubs. the adults eat 8 pounds of meat each day and the cubs eat 4 pounds. how much meat do the cubs and lions eat?

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?

Can some one explain how to slove specifically, what is the value of x? 0.9(x+1.4)-2.3+0.1x=1.6 enter the answer as a decimal in the box. x= ?