The Forestry Club sells Christmas trees each year to raise money for club activities. The trees cost $10 to cut and are sold for $25. Unused trees are stripped of their limbs and sold as firewood for $1 apiece. Data on past sales appear below. How many trees should the forestry club cut this year?
No. of Trees Sold Frequency
10 ...........6
15 ...........3
20 ..............6
25 ...........3
30 ...........2