2x-3y=12
x=4y+1 how do you do this equation?

2-digit numbers less than 91 which are 1 less than a multiple of 10

If, while training for a marathon, you ran 60 miles in 2/3 months, how many miles did you run each month? (assume you ran the same amount each month) write your answer as a whole number, proper fraction, or mixed number in simplest form. you ran __ miles each month.

Bob the builder is making 480kg of cement mix. this is made by cement, sand and gravel in the ratio 1: 3: 4