Simplify the expression 6n2-5n2+7n2

Carrie started with 12 ounces of water when she begin to walk. when she was finish walking she had 2 1/4 ounces of water left. how much did she drank

The lengths of all sides of a triangle are integers when measured in decimeters. one of the sides has length of 1 dm and another of 3 dm. find the perimeter of the triangle.'

Abag of jelly beans contain 13 pink, green, 20 yellow, 10 black, 7 red, and 11 orange jelly beans. approximately what percent of the jelly beans are pink and yellow?