You have to divide 3 by 20. (3/20) Which is also 1.5/10 and as a decimal, that is 15 cents. So one scrunchie is equivalent to 15 cents, which means how many times can you take .15 from 7.25 is how many scrunchies she can buy. So how many times does .15 go into 7.25? The answer is 48.3(repeating). So you have to round it down because if you round it up she needs more money.
![x^ \frac{m}{n} = \sqrt[n]{x^m}](https://tex.z-dn.net/?f=x%5E%20%5Cfrac%7Bm%7D%7Bn%7D%20%3D%20%5Csqrt%5Bn%5D%7Bx%5Em%7D%20)
![((7x^3)(y^2))^ \frac{2}{7} = \sqrt[7]{((7x^3)(y^2))^2}](https://tex.z-dn.net/?f=%20%28%287x%5E3%29%28y%5E2%29%29%5E%20%5Cfrac%7B2%7D%7B7%7D%20%3D%20%5Csqrt%5B7%5D%7B%28%287x%5E3%29%28y%5E2%29%29%5E2%7D%20)
=![\sqrt[7]{((7x^3)^2(y^2)^2)}](https://tex.z-dn.net/?f=%20%5Csqrt%5B7%5D%7B%28%287x%5E3%29%5E2%28y%5E2%29%5E2%29%7D%20)
=![\sqrt[7]{((7^2x^6)(y^4))}](https://tex.z-dn.net/?f=%20%5Csqrt%5B7%5D%7B%28%287%5E2x%5E6%29%28y%5E4%29%29%7D%20)
=![\sqrt[7]{((49x^6)(y^4))}](https://tex.z-dn.net/?f=%20%5Csqrt%5B7%5D%7B%28%2849x%5E6%29%28y%5E4%29%29%7D%20)
=![\sqrt[7]{49x^6y^4}](https://tex.z-dn.net/?f=%20%5Csqrt%5B7%5D%7B49x%5E6y%5E4%7D%20)
