# NCERT Class 8 Mathematics Solutions: Chapter 8 – Comparing Quantities Exercise 8.3 Part 6

Get unlimited access to the best preparation resource for IEO Class-8: fully solved questions with step-by-step explanation- practice your way to success.

**Question: 11** In a laboratory, the count of bacteria in a certain experiment was increasing at the rate of 2.5% per hour. Find the bacteria at the end of 2 hours if the count was initially 5, 06,000.

**Answer:**

Here, Principal (P) = 5, 06,000 Rate of Interest (R) = 2.5%, Time (n) = 2 hours

After 2 hours, number of bacteria

Amount (A)

Hence, number of bacteria after two hours are **531616.25**

**Question: 12** A scooters were bought at ₹ 42,000. Its value depreciated at the rate of 8% per annum. Find its value after one year.

**Answer:**

Here, Principal (P) = Rs. 42,000, Rate of Interest (R) = 8%, Time (n) = 1 years

Amount (A)

Hence, the value of scooter after one year is **Rs. 45,360**