## anonymous 4 years ago An outside circular ring has a circumference of 90 cm. What is the circumference of an inner ring which is 8 cm shorter in radius? Both circles have the same center. i came to 39.8but im barley learning this so just making sure if its wrong don't need to explain just say its wrong thx

1. anonymous

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2. anonymous

${\large{perimeter = 2\times{pie}\times{r}}}$

3. anonymous

@sheg means perimeter of circle. :D And one latex tip to write pi. Write as \pi

4. anonymous

@shivam_bhalla thanks a ton buddy

5. anonymous

oqei thx

6. anonymous

Your approach towards the problem must be to find the radius of outer circle using the formula given by @sheg and then......... @sheg , welcome :)