Do these two questions of math plz(Perimeter and Area)Class 7.Andplz dont spam,who will spam I will report them..And who will give correct answer I will mark him brainliest.with many points.
Answers
Answer:
Circumference of a circle=2xPIEXRADIUS
=2x22/7x21
=132squarecm
If cost of making frame for 1cm is 1.50 means
=132X1.50
=198.00
Therefore 198 rupees needed for framing the mirror
Hope it's helpful
Answer:
12. The answer is ₹750.45
13. The answer is 128cm^2
Step-by-step explanation:
12. Area of the Circular mirror with the frame minus the Area of the circular Mirror.
a. Area of the Circular Mirror with the Frame.
r = radius of the Circular mirror + the width of the circular frame
r = 21 cm + 3.5 cm = 24.5 cm
A = πr^2
A = (3.1416)(24.5 cm)^2 - {use 3.1416 as the value of π then substitute the value of the radius.}
A = (3.1416)(600.25 cm^2) - {(24.5 cm)^2 is equal to 600.25 cm^2}
A = 1885. 7454 cm^2
b. Area of the Circular Mirror itself.
r = 21 cm
Same process.
A = πr^2
A = (3.1416)(21 cm)^2 - {use 3.1416 as the value of π then substitute the value of the radius.}
A = (3.1416)(441 cm^2) - {(21 cm)^2 is equal to 441 cm^2}
A = 1385. 4456 cm^2
c. Subtract: Area of the Circular mirror with the frame minus the Area of the circular Mirror.
Area of the Mirror Frame = 1885. 7454 cm^2 - 1385. 4456 cm^2
Area of the Mirror Frame = 500.2998 cm^2
d. The question is how much is the frame if 1 cm^2 is ₹1.5?
Area of the Mirror Frame multiply by ₹1.5
(500.2998 cm^2) x ₹1.5 = ₹750.45
13. The Illustration is attached.
The problem is the total area of the margin. To find that we need first to find the Area of the Cardboard and the area of the cardboard with the margin.
Then Subtract.
a. Area of the Cardboard with the Margin
The formula for the area of the rectangle is A = lw.
l = 32 cm (28 is the original length but if we add the 2 cm along the sides it will have a length of 32)
w = 19 cm (15 is the original length but if we add the 2 cm along the sides it will have a length of 19)
A = lw = (32 cm)(19 cm) = 608cm^2
b. Area of the Carboard
l =28 cm
w = 15 cm
A = lw = (28cm)(15m) = 420 cm^2
c. Subtract: Area of the Cardboard with the Margin minus Area of the Carboard
Total Area of the Margin = Area of the Cardboard with the Margin - Area of the Carboard
Total Area of the Margin = 608cm^2 - 420 cm^2 = 188 cm^2
