Asked by Sam

A farmer planned to plant 120 seeds in all. After planting 10 more seeds each day than was planned, she was able to finish 2 days earlier. How many seeds were planted each day?
Answered by Steve
If the original plan had been to plant x seeds each day, then

120/x - 2= 120/(x+10)
solve for x.

Or, consider the factors of 120.
which factor is 10 more than another, with the other factors differing by 2?
Answered by Sam
Hi, I tried solving the original equation and got -5 for x and this seemed wrong
Answered by Sam
What did I do wrong?

I would not like the answer but I want to know what to do next
Answered by Steve
clearly a negative value is wrong
I have no idea what you did wrong, since you did not see fit to show your work.

120/x - 2= 120/(x+10)
120(x+10) - 2(x)(x+10) = 120(x)
120x+1200 - 2x^2-20x = 120x
-2x^2+20x+1200 = 0
-2(x-20)(x+30) = 0
x=20

check:
120/20 = 6
120/30 = 4
Answered by Sam
Thats wrong
Answered by Sam
The online thing said no
Answered by R_scott
gosh ... an error in an answer key ... who'd a thunk it

you can either believe a nebulous source ... or your own eyes
Answered by Damon
Ah, Sam, did you happen to notice that the 20 and 30 checked as reported by Steve.
Answered by Steve
It appears that they want the answer to how many seeds were planted to result in the shorter time.
That would be x+10 = 30
Answered by Aaron
After solving the quadratic formula, you get 20 and -30. Now, obviously a negative number doesn't work because no one can plant a negative amount of seeds. So we have 20. The person planted 10 more seeds than what was originally planned, so we have 20+10= 30.
Answered by ITS 30
its 30
There are no AI answers yet. The ability to request AI answers is coming soon!