What is the equivalent fraction of 1/4 using least common denominator

About 400,000 people visited an art museum in december. what could be the exact number of people who visited the art museum?

(if f(x)=4x^2 and g(x)=x+1, find (f o g)(x)

Galen sold tickets of his church’s carnival for a total of $2,820. children’s tickets cost $3 each and adult tickets cost $5 each. the number of children’s tickets sold was 30 more than 3 times the number of adult tickets slod. how many children’s ticket and how many adult tickets did he sell?