# Example 11* (Optional) - Chapter 15 Class 10 Probability

Last updated at Oct. 22, 2018 by Teachoo

Last updated at Oct. 22, 2018 by Teachoo

Transcript

Example 11* (Optional) A missing helicopter is reported to have crashed somewhere in the rectangular region shown in Fig. 15.2. What is the probability that it crashed inside the lake shown in the figure Here, we use area to find probability First, let us find length and height of the lake Length of lake = 9 – 6 = 3 km Breadth of lake = 4.5 – 2 = 2.5 km Now, Area of lake = 3 km × 2.5 km Total Area = 4.5 km × 9 km Now, P (helicopter will fall in lake) = (𝐴𝑟𝑒𝑎 𝑜𝑓 𝑙𝑎𝑘𝑒)/(𝑇𝑜𝑡𝑎𝑙 𝐴𝑟𝑒𝑎) = (3 × 2.5)/(4.5 × 9) = (3 × 25)/(45 × 9) = (1 × 25)/(45 × 3) = (1 × 5)/(9 × 3) = 5/27 So, Probability is 𝟓/𝟐𝟕

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.