the graph below shows the number of visitors who visited science center in the period from July to December.
a) 1200 / 1900 = 12 / 19
b) No. of children = (2/3) (1800) = 1200
Number of boys = 2x
Number of girls = x
So
2x + x = 1200
3x = 1200
x = 1200 / 3 = 400 girls
