Questions

3 Marks Question

Take a timed test

6 questions · self-marked practice — reveal the answer and mark yourself.

Question 13 Marks
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 $77?$
Answer
Let the number of fruit trees be $x.$
According to the question,
$3 \times$ number of fruit trees $+ 2 =$ Number of non-fruit trees
We can write this as,
$3x + 2 = 77$
$3x = 77 – 2$
$3x = 75$
Now,
Dividing both sides by $3,$ we get:
$\frac{3 x}{3}=\frac{75}{3}$
Thus, $x = 25$
Hence, the number of fruit trees was $25.$
View full question & answer
Question 23 Marks
Laxmi’s father is $49$ years old. He is $4$ years older than $3$ times Laxmi’s age. What is Laxmi’s age$?$
Answer
Let Laxmi’s age $= x$ years
$4$ years more than $3$ times Laxmi’s age $= 4 + 3x$
Given Laxmi’s father age $= 49$
According to problem, $4 + 3x = 49$
$3x = 49 – 4 = 45$
$x = \frac{{45}}{3} = 15$
Hence the laxmi's age $= 15$ years.
View full question & answer
Question 33 Marks
Solve the equation by trial and error method: $3m – 14 = 4$
Answer
$L.H.S.$ Value of $m$ Value of $L.H.S.$ $R.H.S.$
$3m – 14$ $0$ $–14$ $4$
$3m – 14$ $1$ $–11$ $4$
$3m – 14$ $2$ $–8$ $4$
$3m – 14$ $3$ $–5$ $4$
$3m – 14$ $4$ $–2$ $4$
$3m – 14$ $5$ $1$ $4$
$3m – 14$ $6$ $4$ $4$

So, $m = 6$ is the solution of the given equation $3m – 14 = 4.$
View full question & answer
Question 43 Marks
Check whether the value given in the bracket is a solution to the given equation or not.
$7n + 5 = 19 (n = –2)$
Answer
$7n + 5 = 19 (n = –2)$
$L.H.S. = 7n + 5$
$= 7 (–2) + 5 . . . . [$ When $n = –2]$
$= –14 + 5$
$= –9$
$R.H.S. = 19$
$\because L.H.S. \neq R.H.S.$
$\therefore n = –2$ is not a solution to the given equation $7n + 5 = 19.$
View full question & answer
Question 53 Marks
Find a number, such that one-fourth of the number is $3$ more than $7.$
Answer
Let the unknown number to be $y.$
one-fourth of $y$ is $\frac{y}{4}$.
According to question,
This number $\left(\frac{y}{4}\right)$ is $3$ more than $7.$
Hence, the equation for $y$ is $\frac{y}{4}– 7 = 3$
Adding $7$ to the both sides of the equation, we get,
$\frac{y}{4}=3+7=10$
Multiply both sides of the equation by $4,$ we get,
$\frac{y}{4} \times 4=10 \times 4$
or $y = 40$
View full question & answer
Question 63 Marks
Raju’s father’s age is $5$ years more than three times Raju’s age. Find Raju’s age, if his father is $44$ years old.
Answer
Let Raju's age be $y$ years.
Three times Raju’s age is $3y$ years.
Raju’s father’s age is $5$ years more than $3y$
Therefore, Raju’s father's age $= (3y + 5)$ years
Also, given that Raju’s father is $44$ years old.
Therefore, $3y + 5 = 44.$
To solve it, we first transpose $5,$ to get
$3y = 44 – 5 = 39$
Dividing both sides by $3,$ we get $y = 13$
Therefore, Raju’s age is $13$ years.
View full question & answer