Tom's mark of a maths test was 68.this was 20% worse than his mark in english. what was tom's english mark ?

How many solutions does the nonlinear system of equations graphed below have?

Emily is entering a bicycle race for charity. her mother pledges $0.90 for every 0.75 mile she bikes. if emily bikes 18 miles, how much will her mother donate?

Hurry if the population of of an ant hill doubles every 10 days and there are currently 100 ants living in the ant hill what will the ant population be in 20 days