Add 5 and 14 , triple the sum and then add four fifth

Find all the values of x that make 0.1x + 0.25(102 - x) < 17.10 true.

Which of the following is the equation that says that the product of a number and ten is equal to 20 percent of that number ? a) 10n= 2.0n b) 10+n=.20n c) n+ .20n=10 d) 10n=0.20n

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'