Reading fractions from a pie chart

The pie chart shows the cartons of milk a school canteen sold in a week. The canteen sold two hundred and forty cartons altogether. The plain milk part is marked with a right angle. Find the number of plain milk cartons, then the fraction that were banana milk, in its simplest form. Try it first. Pause if you like. From the pie chart, ninety-six cartons were chocolate milk and fifty-four were strawberry milk. The plain milk part has no number. What does the small right-angle square tell us? Watch this quarter-circle guide go around the same whole. Four equal quarters fit around one circle. The right angle shows that one quarter of the cartons were plain milk. Plain milk is two hundred and forty divided by four, which equals sixty. Sixty cartons of plain milk were sold. For banana milk, which known parts must be subtracted from the whole? Banana milk is two hundred and forty minus sixty minus ninety-six minus fifty-four, which equals thirty. The fraction of banana milk is thirty over two hundred and forty. Divide the numerator and denominator by thirty to get one eighth. One eighth of the cartons were banana milk. The marked quarter was a known part too. We included plain milk before finding what was left.

The pie chart shows four workshops chosen by pupils at a holiday camp. Two hundred pupils chose a workshop altogether. Baking is one half of the chart. Robotics is marked with a right angle, and thirty pupils chose batik. Find how many pupils chose origami, then what fraction chose origami. Give the fraction in its simplest form. Try it first. Pause if you like. From the pie chart, thirty pupils chose the batik workshop. The straight line through the centre cuts the whole circle into two equal halves. Watch the half-circle guide match each side. The pie chart is cut into halves, so one half of the pupils chose the baking workshop. Baking is two hundred divided by two, which equals one hundred. Now look at robotics. Its right-angle square marks a quarter of the same whole circle. The right angle shows that one quarter of the pupils chose the robotics workshop. Robotics is two hundred divided by four, which equals fifty. We know the baking, robotics and batik parts. What remains for origami? Origami is two hundred minus one hundred minus fifty minus thirty, which equals twenty. Twenty pupils chose the origami workshop. The fraction for origami is twenty over two hundred. Divide the numerator and denominator by twenty to get one tenth. One tenth of the pupils chose the origami workshop. Read the half and quarter first. Subtract every known part, then simplify the fraction.