How many two digit whole numbers can be written as the sum of two different single digit whole numbers? Lots of points, and will
2 answers:
You want . We can go about this by casework. WLOG x=9, we have 8 digits: 1-8. With x=8 we have 2-9, but we already counted 8 and we already considered the 9 case, so we have 2-7 actually, which will give us 6 numbers. With x=7, with the same logic we are only looking for the numbers 3-6 which there are 4 of. With x=6, you are looking for the numbers 4-5 which are 2. With x=5 run out of numbers to pick. The numbers are indistinguishable and it does not matter whether we use x or y so we just have to ad up the cases we already have to get: 20.
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Answer:
Option a :
Step-by-step explanation:
Given :
The drama club sold 100 tickets to a show, it had $300 in profit.
The next show, it had sold a total of 200 tickets and had a total of $700 profit.
To Find : Equation models the total profit, y, based on the number of tickets sold, x
Solution :
For 100 tickets he had $300 in profit .
⇒ ()=(100,300)
For 200 tickets he had $700 in profit .
⇒ ()=(200,700)
We will use point slope form i.e.
--(A)
Now, to calculate m we will use slope formula :
Now, putting values in (A)
Thus Option a is correct i.e.