Can someone turn 6/15 and 14/16 into their lowest forms?

Aswim teacher sells lesson packages. the best deal has the highest ratio of lessons to total cost.swim lesson packagesnumber of lessons total cost$10$4010 1 $8015$80which package is the best deal? l lesson for $105 lessons for $4010 lessons for $8015 lessons for $80mark this and returnsave and exit

Christina can paint 420 square feet in 105 minutes. which unit rate describes the scenario?

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?