XAT 2018 — QA & DI Question 6
MiscellaneousEasy
A coin of radius 3 cm is randomly dropped on a square floor full of square shaped tiles of side 10 cm each. What is the probability that the coin will land completely within a tile? In other words, the coin should not cross the edge of any tile.
Answer & solution
- A
0.91
- B
0.5
- C
0.49
- D
0.36
0.16
Solution
Let’s consider one of the tiles with side 10 cm. For the coin to land completely within the tile, its centre should fall anywhere inside the square of side 4 cm.
âââââââ
∴ Favourable area = 4 × 4 = 16
Total area available = 10 × 10 = 100
∴ Required probability = 0.16
Hence, option (e).