In the verge of coronavirus pandemic, we are providing FREE access to our entire Online Curriculum to ensure Learning Doesn't STOP!

Ex.4.4 Q3 Simple-Equations Solution - NCERT Maths Class 7

Go back to  'Ex.4.4'

Question

Solve the following:

(a) Irfan says that he has \(7\) marbles more than five times the marbles Parmit has. Irfan has \(37\) marbles. How many marbles does Parmit have?

(b) Laxmi's father is \(49\) years old. He is \(4\) years older than three times Laxmi's age. What is Laxmi's age?

(c) People of Sundargram planted trees in the village garden. Some of the trees were fruit trees. The number of non-fruit trees were two more than three times the number of fruit trees. What was the number of fruit trees planted if the number of non-fruit trees planted was \(77\)?

 Video Solution
Simple Equations
Ex 4.4 | Question 3

Text Solution

What is known?

Statement of the question.

What is unknown?

Equation and the value of the variable.

Reasoning:

Make suitable equation using the given information and then solve the equation.

Steps:

(a) Number of marbles Parmit has \(37\). Let the number of marbles Parmit has be \(x\). According to question,

\[\begin{align}5x  + 7 &= 37\\5x &= 30\\x = \frac{{30}}{5} &= 6\end{align}\]

Therefore, Parmit has \(7\) marbles

(b) Let the age of Laxmi be \(x\). Age of Laxmi’s father be \( 49\) years

According to question,

\[\begin{align}3x + 4 &= 49\\3x = 49 \,– 4 &= 45\\x = \frac{{45}}{3} &= 15\end{align}\]

Therefore, Laxmi’s age is \(15\) years

(c) Let the number of fruit tress be \(x\). Then the number of non-fruit trees are \(3x +2\)

According to question,

\[\begin{align}3x + 2 &= 77\\3x = 77 - 2&= 75\\x = \frac{{75}}{3} &= 25\end{align}\]

The number of fruit trees planted are \(25\).

  
Learn from the best math teachers and top your exams

  • Live one on one classroom and doubt clearing
  • Practice worksheets in and after class for conceptual clarity
  • Personalized curriculum to keep up with school