Example 5 (Page 66) - Chapter 3 Class 8 - Proportional Reasoning-2 (Ganita Prakash II)

Transcript

Example 5 (Page 66) A school has food provisions to feed 80 students for 15 days. If 20 more students join the school, for how many days will the provisions last?Given that, 80 students have food provisions for 15 days We need to find much time would food provisions last if 20 more students join So, Total students are now = 80 + 20 = 100 Let the Time taken be y hours Now, we draw a table Now, as quantity of food is same As Number of students increase Time for Food provisions lasting would decrease So, they are in Inverse Proportion So, we write numbers as 𝒙_𝟏 𝒚_𝟏 = 𝒙_𝟐 𝒚_𝟐 80 × 15 = 100 × 𝑦 (80 × 15)/100=𝑦 (4 × 15)/5=𝑦 12 = 𝑦 𝒚 = 12 So, food provisions will last 12 days