MCQ Practice Mathematics 📖 Francis had an average of 75 on her first four Geometry test. After taking the next test her average dropped to 72. How much ... Favorite Practice Add to Book Explanation & Answer Detailed explanations and answers are restricted. Unlock full access by logging in to your account. 🔒 Unlock the detailed explanation and answers Log In / Sign Up PreviousAverage weight of 8 persons is 120 lb. One person leaves the group and a new person comes in and the new average is 122 lb. I... NextIf 3a +5b = 10 and 5a + 3b = 30, what is the average (arithmetic mean) of a and b?