Computed new Food amount = $140 and treated it as 100 units out of 360 by dividing 360 by ($400 / $140) approximation, mis-converting to degrees.
PRIMARY 6 · MATHEMATICS
Pie Charts
Top 5 mistakes
Ranked by how often they appear across 47 MOE-aligned practice questions in our archive.
Mistook the $20 transfer as 5% of the WHOLE pie and subtracted 5% off the original 40% as an angle: 40 - 5 = 35 percent, then computed 35 x (360 / 100) - 1 = 125° and rounded to 135°.
Used the ORIGINAL Food percentage 40% and converted directly to degrees: 0.40 x 360 = 144°, ignoring the $20 transfer out of Food.
Took only potato 1/5 of 540 = 108 and reported that as the vegetable count.
Took only chicken 1/4 of 540 = 135 and reported that as the vegetable count.
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