List of the first few prime numbers greater than 3:
5, 7, 11, 13, 17, 19, 23, 29
Now find the combination that you can multiply and still have a 2 digit number:
5 x 7 = 35
5 x 11 = 55
5 x 13 = 65
5 x 17 = 85
5 x 19 = 95
5 x 23 = 115 ( 3 digit number, can't use).
7 x 5 = 35
7 x 11 = 77
7 x 13 = 91
7 x 19 = 133 ( 3 digit number, can't use).
The largest 2 digit number would be 5 x 19 = 95
There is no solution for the first one
if you eliminate y you get 2 equations
-13x - 13z = -25
-13x - 13x = -15
- there is no solution to theses
a23 means the element in the second row and the 3rd column
so its -5
Answer:
120
Step-by-step explanation:
Krutika:48
David: 48
Mark: 48÷2= 24
Because 2 : 2 : 1
48+48+24=120
<h3>
Answer: n+15</h3>
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Explanation:
- n = number of minutes
- cost of company X = 3n+30
- cost of company Y = 2n+15
To find out how much more company X charges, we subtract the two cost expressions
CompanyX - CompanyY = (3n+30)-(2n+15) = 3n+30-2n-15 = n+15 which is the final answer.
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An example:
Let's say you talk on the phone for n = 20 minutes.
Company X would charge you 3n+30 = 3*20+30 = 90 cents
Company Y would charge you 2n+15 = 2*20+15 = 55 cents
The difference of which is 90-55 = 35 cents.
If you plugged n = 20 into the n+15 expression we got, then n+15 = 20+15 = 35 matches up with the previous 35 cents.
This example helps confirm the answer. I'll let you try out other examples.
