JEE MainPhysicsUnits and MeasurementsMCQ+4 / −1
The area of a square is 5.29 cm2. The area of 7 such squares taking into account the significant figures is :-
- A37.0 cm2
- B37 cm2
- C37.030 cm2
- D37.03 cm2
View written solutionFree
Correct answer: A
-
Given data
Area of one square =
Number of squares =
-
Find total area
-
Apply significant figures rule
In multiplication, the result should have the same number of significant figures as the factor with the least number of significant figures.
- has 3 significant figures.
- is a counted number (exact number of squares), so it does not limit significant figures.
Therefore, the answer should be reported with 3 significant figures.
-
Round the result
since has 3 significant figures.
-
Check options
- A: ✅
- B: has only 2 significant figures ❌
- C: has too many significant figures ❌
- D: has too many significant figures ❌
Hence, the correct answer is A.
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