Punjab State Board PSEB 8th Class Maths Book Solutions Chapter 15 Introduction to Graphs InText Questions and Answers.
PSEB 8th Class Maths Solutions Chapter 15 Introduction to Graphs InText Questions
Try These : [Textbook Page No. 244]
1. In the above example, use the graph to find how much petrol can be purchased for ₹ 800.
Solution:
We can find the quantity of petrol to be got for ₹ 800. For this take a point on the Y-axis (0, 800). Now, draw a line parallel to X-axis to meet the graph at the point B. Now, from the point B, draw a line parallel to Y-axis, which intersect X-axis in the point C. Coordinate of the point C : (16, 0).
Hence, 16 litres of petrol can be purchased for ₹ 800.
Think, Discuss and Write : [Textbook Page No. 243]
1. The number of litres of petrol you buy to fill a car’s petrol tank will decide the amount you have to pay. Which is the independent variable here? Think about it.
Solution:
Here, we clearly understand that graph of quantity of petrol (litre) and amount to pay (₹) should be a line.
Both quantities are in direct proportion. If we fill more litres of petrol, we have to pay more amount and vice versa.
∴ Petrol is the independent variable.
Try These : [Textbook Page No. 245]
1. Is Example 7, a case of direct variation?
Solution:
Yes, Example 7 given on page 245 (Textbook), is a case of direct variation. As the principal increases, the simple interest on it also increases proportionately.