How can you tell before you divide 425 by 9 that the first digit of the quotient is in the tens place

If there are 12 moths and some have 31 days and others have 30 days how many have 28 days?

How do you solving the solution of each system using elimination?

Suppose you are an avid reader and are looking to save money on the cost of books instead of paying about $20 for each book, you decide to look into purchasing a kindle for $120 you can purchase e-books for about $5 each 1. find the slope-intercept equation for the cost of the hard copy of books using x to represent the number of books 2. find the slope-intercept equation for the cost of the kindle with cost of e-books using x to represent the number of books