the area of the path between two concentric circle is 770 CM square and the sum of circumference of the two circle is 220 cm find the width of the part between them
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circumference=2πr
circumference of bigger circle=2πR
circumference of smaller circle=2πr
according to question
2πr+2πR=220
2π(r+R)=220
π(r+R)=110
area of path=area of bigger circle-area of smaller circle
area of circle =πr^2
area of bigger circle =πR^2
area of smaller circle=πr^2
770= πR^2-πr^2.
770=π(R^2-r^2)
770=π{(R+r)(R-r)}. (a^2-b^2=(a+b)(a-b)
770=π(R+r)+π(R-r)
put value of π(R+r)
770=110+π(R-r)
770-110=π(R-r)
660×7/22=R-r
210=R-r
width of path=R-r
=210
circumference of bigger circle=2πR
circumference of smaller circle=2πr
according to question
2πr+2πR=220
2π(r+R)=220
π(r+R)=110
area of path=area of bigger circle-area of smaller circle
area of circle =πr^2
area of bigger circle =πR^2
area of smaller circle=πr^2
770= πR^2-πr^2.
770=π(R^2-r^2)
770=π{(R+r)(R-r)}. (a^2-b^2=(a+b)(a-b)
770=π(R+r)+π(R-r)
put value of π(R+r)
770=110+π(R-r)
770-110=π(R-r)
660×7/22=R-r
210=R-r
width of path=R-r
=210
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this is the answer if u want you can check the answer by putting the value of r1 and r2 and subtract their areas u will get 770cm^2.and if u feel that my answer is correct then please mark me as brainliest.
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