Question

At a gig 0.4 of the audience were female. If there were 100 more male audience members than female, how many were there in the audience?

Answer 1

Number of females = f
Total number of people in audience = n

0.4n = f
f + (f+ 100) = n
2f + 100 = n

Find n:
f = 0.4n --> Replace f with 0.4n in the equation 2f +100 = n

2(0.4n) + 100 = n --> Multiply out the brackets
0.8n + 100 = n --> Subtract 0.8n from both sides
100 = 0.2n --> To get n, multiply both sides by 5
n = 500

There were 500 people in the audience.