Question 7 - Mind the Mistake, Mend the Mistake - Chapter 7 Class 7 - Finding the Unknown (Ganita Prakash II)

Transcript

Question 7 The following are some equations along with the steps used to solve them to find the value of the letter−number. Go through each solution and decide whether the steps are correct. If there is a mistake, describe the mistake, correct it and solve the equation.Is there a mistake? Yes What went wrong? The student tried to subtract 2 from 50. You cannot touch the +2 yet because it is locked inside the brackets multiplied by 4. Correct solution Now, 4(4q + 2) = 50 Opening bracket 4 × 4q + 4 × 2 = 50 16q + 8 = 50 Taking 8 on right side, it becomes subtraction 16q = 50 – 8 16q = 42 Taking 16 on right side, it becomes division q = 42/16 q = 𝟐𝟏/𝟖