Question 5 - End-of-Chapter Exercises - Chapter 2 Class 9 - Introduction to Linear Polynomials (Ganita Manjari

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Question 5 If you have ₹800 and you save ₹250 every month, find the amount you have after (i) 6 months (ii) 2 years. Express this as a linear pattern. Given that we have ₹800 and you save ₹250 every month, Thus, Initial Value = ₹ 800 Value after 1 month = 800 + 250 = ₹ 1,050 Value after 2 months = 800 + 250 × 2 = 800 + 500 = ₹ 1,300 Value after 3 months = 800 + 250 × 3 = 800 + 750 = ₹ 1,550 Similarly, we can write Value after 6 months = 800 + 250 × 6 = 800 + 1500 = ₹ 2,300 We also need to find value after 2 years Since 2 years = 2 × 12 months = 24 months We can write Value after 2 years = Value after 24 months = 800 + 250 × 24 = 800 + 6,000 = ₹ 6,800 We are also asked to express it as a linear pattern When we say linear pattern, we mean linear relationship Let Time in months = t And, value of money (in ₹) after t months be v(t) Since value v starts at ₹ 800 and adds ₹250 every year t. Our Expression is v(t) = 800 + 250t