Ihave four factors three of my factors are 12 and 10 what is my fourth factor

Find the area of a trapezoid with a height of 23, base 1 of 10 and base 2 of 18

Barbara's piano instructors house is 7 1/8 miles from her house. after biking for 1 3/4 miles she stops to rest how much longer does she need to bike to reach her instructor's house

Kathy spent 5/8 of her money on books and another 1/6 of her money on stationeries.what fraction of kathy’s money was left?