59. 40% of deaths on city roads may be attributed to drunken driving. The number of degrees needed to
represent this as a slice of a pie chart is
(a) 120 (b) 144
(c) 160 (d) 212
Pie Chart Angle for 40% Drunken Driving Deaths: Calculation and Exam Solution
A pie chart represents the full 360 degrees of a circle proportionally to data percentages, so 40% of city road deaths from drunken driving translates to 40% of 360°, which equals 144 degrees. This multiple-choice question tests basic data interpretation skills common in competitive exams like GATE. The correct answer is option (b) 144.
Calculation Method
The standard formula for a pie chart slice angle is:
Angle = (Percentage / 100) × 360°
For 40%:
(40 / 100) × 360 = 0.4 × 360 = 144°
This works because 1% equals 3.6° (360/100), so 40 × 3.6 = 144°.
Option Analysis
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(a) 120°: Equals one-third (120/360 ≈ 33.3%), underestimating the 40% share.
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(b) 144°: Matches exactly, as shown in the formula.
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(c) 160°: Overshoots to about 44.4% (160/360), a common miscalculation like using 360 × 0.44.
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(d) 212°: Far too high at nearly 59% (212/360), possibly from confusing with 360 – (40% of something else).
