Find Live Listings for Digit Saver on eBay Below
 |
No items matching your keywords were found.
Scroll Down to Find Even More Digit Saver Below
HELP WITH MATH!!!!!!!!?
Ok so this question is a long one, that's why i got confused
Ok it's:
Let P(n) and S(n) denote the product and the sum, respectively, of the digitsof the integer n. For example, P(23) = 6 and S(23) = 5. Suppose N is a two-digit number such that N = P(N) +S(N). What is the units digits of N?
If you help you will be a life saver...thanks so much!!
Let us first assign variables:
x = tens digit of N
y = units digit of N
Thinking about it logically, the number N would be represented by the expression 10x + y, since every time you have a two digit number, the digit in the tens place is technically multiplied by ten.
(example, 63 = (6 * 10) + 3)
N = 10x + y
Now, P(N) is the product of the two digits, therefore:
P(N) = xy
S(N) is the sum of the two digits, therefore:
S(N) = x + y
Now since you know N = P(N) + S(N), you can put it all together.
10x + y = xy + (x + y)
10x + y - x - y = xy
9x = xy
y = 9
Since you're only looking for the units digit, and y is the units digit, you're done. The units digit of N would simply be 9.
|
No items matching your keywords were found.
