Answer:
a. -3.78x-0.84
Step-by-step explanation:
To simplify, combine like terms. Because you're just adding them you don't have to change any signs. Add/subtract the terms with an x, that will give you your first number, then add/subtract the terms without an x to get your second number.
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,
we have
the solution is the interval -------> (3,∞)
therefore
the answer in the attached figure
