Question 8 - Figure it out - Page 67, 68 - Chapter 3 Class 8 - Proportional Reasoning-2 (Ganita Prakash II)

Transcript

Question 8 A given set of chairs are arranged in 25 rows, with 12 chairs in each row. If the chairs are rearranged with 20 chairs in each row, how many rows does this new arrangement have?Given that, There are 25 rows, with 12 chairs in each row We need to find how many rows are there if there are 20 chairs in each row Let Number of Rows be x Now, we draw a table Now, as Total number of chairs is same As Chairs per rows increase Number of rows would decrease So, they are in Inverse Proportion So, we write numbers as 𝒙_𝟏 𝒚_𝟏 = 𝒙_𝟐 𝒚_𝟐 25 × 12 = 𝑥 × 20 (25 × 12)/20=𝑥 (5 × 12)/4=𝑥 15 = 𝑥 𝒙 = 15 So, there are 15 rows