NCERT Exemplar Solutions
Class 7 - Mathematics - Unit 4: Simple Equations - Problems and SolutionsQuestion 79
Class 7 - Mathematics - Unit 4: Simple Equations - Problems and Solutions
Question. 79
My younger sister's age today is 3 times, what it will be 3 years from now minus 3 times what her age was 3 years ago. Find her present age.
Answer:
18 years
Detailed Answer with Explanation:
Let present age = x.
x = 3[(x + 3) − (x − 3)] ⇒ x = 3(6) = 18.