At the science museum there is an energy exhibition with 150 displays: • 30% of the displays are about electricity • 2 5   are about using renewable energy • 0.2 are about the use of gas • the remainder are about nuclear power how many displays are there about nuclear power?

There should be 50 displays about nuclear power
30% of 150 is 45
45+25=70
.2% or 20% of 150 is 30
70+30=100 
So there are 50 left over which are the nuclear powers

Google it that might work

1. isolate the variable, in this case, d. subtract 35.5 on both sides of the equation.2. 52 subtracted by 35.5 is 16.53. therefore your answer would be d= 16.5this is the basics of pre algebra, isolating variable through adding, subtracting, multiplying, and dividing, if you have any other questions to ask just comment!