+129852 We can do this by working out the areas of the rectangles = base * height
Rectangle 6 -10 .....base = 4 and height = 3....area = 12
Rectangle 10-12 ....base = 2 and height = 8....area = 16
Rectangle 12 - 14 ....base = 2 and height = 11.....area = 22
Rectangle 14 -15......base = 1 and height = 23...area = 23
Rectangle 15 - 16 .....base = 1 and height = 19 ....area = 19
Rectangle 16 - 20...base = 4 and height = 2....area = 8
Number of mice below 10g =
[ Area of rectangle 6-10] / [ Area of all rectangles] * 1000 =
[ 8 ] / [ 12 + 16 + 22 + 23 + 19 + 8 ] * 1000 =
[ 8 ] / [100] * 1000 = 8000 / 100 = 80 mice
