A tree is growing at a constant rate. It is recorded that at the 7th year since it was planted it was at a height of 25 feet. It was recorded again at the 10th year since it was planted and it was at a height of 31 feet. How tall was the tree when it was first planted.

Data from 2005 for various age groups show that for each $100 increase in the median weekly income for whites, the median weekly income of blacks increases by $105. also, for workers of ages 25 to 54 the median weekly income for whites was $676 and for blacks was $527. (a) let w represent the median weekly income for whites and b the median weekly income for blacks, and write the equation of the line that gives b as a linear function of w. b = (b) when the median weekly income for whites is $760, what does the equation in (a) predict for the median weekly income for blacks?

Tom can paint the fence in 12 hours, but if he works together with a friend they can finish the job in 8 hours. how long would it take for his friend to paint this fence alone?

What percent of 18 is 24? and plz explain thx.