WAEC Mathematics 2022 Theory — Question 3
Question 3 of 13 from the West African Examinations Council (WAEC) Mathematics 2022 Theory paper, with the correct answer and a full explanation.
Advertisement
3. The diagram shows triangle PQR inscribed in a circle. A chord subtends an angle of 72° at the centre of a circle of radius 24.5m. Calculate the perimeter of the minor segment. [Take π=22/7].
Model answer
Perimeter of minor segment = length of arc AB + 2|MB|. Length of arc |AB| = (θ/360)×2πr = (72/360)×2×(22/7)×24.5 = 30.8m. To find |MB|: sin36° = |MB|/24.5, so |MB|=24.5×sin36°=14.401m. Perimeter = 2(14.401)+30.8 = 59.6m.
Advertisement
Sign up free to unlock
- Score tracking
- Practice history
- Saved questions
- Progress dashboard
- Personalized sessions
- Weak-topic breakdown
…and/or go further with premium services and No Ads.