Mathematics
The external and internal radii of a ring shaped metal sheet are 10 cm and 8 cm respectively. The area of its one face, in terms of π is :
36π cm2
64π cm2
100π cm2
168π cm2
Answer
Given:
Radius of outer circle = 10 cm
Radius of inner circle = 8 cm
Area of circular ring = Area of outer circle - Area of inner circle
As we know, the area of the circle = πr2
⇒ Area of circular ring = π x (10)2 - π x (8)2
= 100π - 64π
= 36π cm2
Hence, option 1 is the correct option.
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Statement 1: ABCD is a parallelogram, base AB = 12 cm, perpendicular dropped from D to AB is 9 cm, area of parallelogram ABCD = 54 cm2.
Statement 2: The area of parallelogram = Base x Height.
Which of the following options is correct?
Both the statements are true.
Both the statements are false.
Statement 1 is true, and statement 2 is false.
Statement 1 is false, and statement 2 is true.