I suppose you want to know such number. Since we have a two digit number consisting of two consecutive integers, the only possible numbers are:
Since we sorted all the cases out, we simply have to check which one satisfies the requirement. For each number, we'll write four times the the sum of its digits, and add 6, hoping to get the original number.
So, the answer is 34.
Answer:
5 more than 30 trees should be planted, for a total of 40 trees per acre.
Step-by-step explanation:
Let x be the number of trees beyond 30 that are planted on the acre
The number of oranges produced = Oranges(x) = (number of trees) (yield per tree)
We are given that For each additional tree in the acre, the yield is reduced by 7 oranges per tree
So, number of oranges produced =
=
=
The derivative Oranges'(x) = 100-20x
Substitute first derivative equals to 0
Using the second derivative test,
Oranges"(x) = -20
20 is negative,
So, this is the case of maximum.
Thus, 5 more than 30 trees should be planted, for a total of 40 trees per acre.