You need to differentiate the equation to find the answer
To do groups of 9, she could make 2 rows of 9. To do 3, she could do 6 rows of 3. Last, to do 6 she could do 3 rows of 6. :)
Answer:
4.5 x 30 = 135
0.1 x 30 = 3
Hint: something multiplied by 0.1 is the same as that same thing divided by 10.
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Formula
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Area of circle = πr²
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Find radius
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πr² = 75
r² = 75 ÷ π
r² = 23.87
r = √23.87
r = 4.89 cm (nearest hundreds)
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Answer : radius = 4.89cm
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