Download App

Concept of Perimeter and Area — MATHS STD 6 — Question

Gujarat BoardEnglish MediumSTD 6MATHSConcept of Perimeter and Area1 Mark
MCQ
Mark $(\checkmark)$ against the correct answer in the following: The area of a rectangular carpet is $120m^2$ and its perimeter is $46m$. The length of its diagonal is:
Hint: $l + b = 23$ and $lb = 120$ Diagonal $=\sqrt{\text{l}^2+\text{b}^2}=\sqrt{289}$ $=\sqrt{17\times17}=17$
  • A
    $15m$
  • B
    $16m$
  • ✓
    $17m$
  • D
    $20m$
✓

Answer

Correct option: C.
$17m$
Area of rectangular carpet $= 120cm^2$
Perimeter $= 46m$
Now $2(l + b)$
$= 46m$
$\Rightarrow \text{l}+\text{b}=\frac{46}{2}=23$
and $lb = 120$
$\therefore (\text{l}-\text{b})^2=(\text{l}+\text{b})^2-4\text{lb}$
$=(23)^2-4\times120$
$=529-480$
$=49=(7)^2$
$\therefore \text{l}-\text{b}=7$
and $l + b = 23$
Adding we get, $2l = 30$
$\Rightarrow \text{l}=\frac{30}{2}$
$=15$
$\therefore b = 23 - 15 = 8$
Now diagonal $=\sqrt{\text{l}^2+\text{b}^2}$
$=\sqrt{(15)^2+(8)^2}$
$=\sqrt{225+64}$
$=\sqrt{289}$
$=17\text{m}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q. [1 Marks Each]" from Concept of Perimeter and Area→Concept of Perimeter and Area — all question types→MATHS STD 6 question papers→Gujarat Board STD 6 question papers→Gujarat Board question paper generator→

Similar questions

Mark $(\checkmark)$ against the correct answer in the following.
If $24$ workers can build a wall in $15$ days, how many days will $8$ workers take to build a similar wall?
→
What percent of $8.25m$ is $75\ cm?$
→
$\frac{7}{100}$ is equal to:
→
Expanded form of $78.059$ is.
→
If $\text{A}=\pi(\text{R}^2-\text{r}^2)$ than R is equal to.
→
Mark the correct alternative in the following: Which of the following numbers is not divisible by $4$?
→
$9798745995$ is written with periods in international system as __________.
→
The additive identity element in the set of integers is
→
The product of the place values of two $2’s$ in $428721$ is:
→
Place value of $9$ in $7, 92, 83, 456$
→