How do i do this numbers 26-28 like what equation would u use to solve

Louise measured the perimeter of her rectangular scrapbook to be 154 cm. if the scrapbook is 45 cm wide, how long is the scrapbook?

The weights of broilers (commercially raised chickens) are approximately normally distributed with mean 1387 grams and standard deviation 161 grams. what is the probability that a randomly selected broiler weighs more than 1,425 grams?

Simplify. 4+3/7x-2-2/7x a. 2-5/7x b. 6-1/7x c. 2+1/7x d. 6+5/7x