Question 47

An umbrella is made by stitching together 10 triangular pieces of cloth, 5 of each of two different colours. Each piece has sides of 30 cm, 60 cm and 60 cm. How much cloth of each colour is needed to make the umbrella?

s = $$\ \frac{\ a+b+c}{2}$$ = $$\ \frac{\ 30+60+60}{2}$$ cm =75 cm
Using Heron's formula
Area=√[s(s-a)(s-b)(s-c)]
=√[75(75-60)(75-60)(75-30)]
=$$225\sqrt{\ 15}$$ cm
There are total 10 pieces 

First colour=5*($$225\sqrt{\ 15}$$) = $$1125\sqrt{15}$$ cm
Second colour=5*($$225\sqrt{\ 15}$$) = $$1125\sqrt{15}$$ cm

B is the correct answer.

Was this solution helpful?

Get AI Help

Create a FREE account and get:

  • All Quant Formulas and shortcuts PDF
  • 200+ previous papers with solutions PDF
  • Top 5000+ MBA exam Solved Questions for Free

Related Formulas With Tests

Book Free CAT Mentorship

Get personalized CAT strategy from a 99%iler

500+ students mentored
CAT mentor

Join CAT 2026 course by 5-Time CAT 100%iler

Start your IIM journey with the right preparation and crack CAT 2026.

Ask AI