Alexa and her friends went out for pizza to celebrate the softball team’s victory.  Their total bill for the pizza and drinks was $32.50.  If they left a 20% tip for their server, how much tip did they leave? How do I solve this problem? ​

Imagine a new pasture with grass growing on it. every day after the seeds have germinated, the number of blades of grass in the pasture triples. after 18 days, the entire pasture is completely covered in grass. how many days did it take for the pasture to be one-third covered in grass?

In trapezoid efgh, m∠hef=(4x2+16)∘ and m∠gfe=(5x2+12)∘. find the value of x so that efgh is isosceles.

Can you simplify 4/7? 24 points will be awarded!