Evaluate 3/7 of 581 - 0.35 x 480 Anyone know how to work it out

Cody worked 42.5 hours per week in july. this is 12.25 hours more per week than he worked in june.how many hours did cody work per week in june?

One-third of the people from country a claim that they are from country b, and the rest admit they are from country a. one-fourth of the people from country claim that they are from country a, and the rest admit they are from country b. in a combined census of the two countries, one-half of the total claimed to be from a. what is the ratio of the populations of country a to that of country b.

One card is dealt from a 52 card deck. find the probability that the dealt card is a 4 or a black 7