A)
Let X be the food expenditure of a family.
Let the population mean of an expenditure of a family be.
Let the population standard deviation of an expenditure of a family be.
The proportion families spend more than $30 but less than $490 per month on food is,
To find the side lengths, you have to factor 4x^2 + 28x + 49. This equation factored is (2x+7)(2x+7), so each side length is (2x+7) feet.
228 - 48 = 180
180/48 = 3.75
Its increase 375%
