Alright so I'm coming up with this on the fly; you have the first six letters (a,b,c,d,e,f) and 0-9 and your ten numbers. calculate the amount of possible combinations for the letters by simply writing them down.
ab, ac, ad, ae, a f- five
bc, bd , be, bf- four
cd, ce, cf- three
de, df- two
ef,- one.
adding these all together gets a total of 15 for the letters. now the numbers
01, 02, 03, 04, 05, 06, 07, 08, 09- nine
12, 13, 14, 15, 16, 17, 18, 19- eight
23, 24, 25, 26, 27, 28, 29- seven
34, 35, 36, 37, 38, 39- six
45, 46, 47, 48, 49- five
56, 57, 58, 59- four
67, 68, 69- three
78, 79- two
89- one
added together with a total of 45 combinations.
alright so, 45 different number combinations and 15 letter combinations. multiplying 15 by 45 should tell you the total possible combinations for a two letter and two number serial-number
Answer:
13 children and 9 adults if the total cost is $152.5
Step-by-step explanation:
Let x children and y adults
x + y = 22 (1)
5.5x + 9y = 125.5 (2)
y = 22 - x
5.5x + 9(22 - x) = 125.5
5.5x + 198 - 9x = 125.5
-3.5x = 125.5 - 198
-3.5x = -72.5
x = 20.7
y = 22 - x = 1.3
Which is not possible
If the total cost is $152.5
x + y = 22 (1)
5.5x + 9y = 152.5 (2)
y = 22 - x
5.5x + 9(22 - x) = 152.5
5.5x + 198 - 9x = 152.5
-3.5x = 152.5 - 198
-3.5x = -45.5
x = 13
y = 22 - 13 = 9
<u>Answer:</u>
- The solution to the equation is 4.
<u>Step-by-step explanation:</u>
<u>Work:</u>
- 6x - 3 = 21
- => 6x = 21 + 3
- => 6x = 24
- => x = 4
Hence, <u>the solution to the equation is 4.</u>
Hoped this helped.

Answer:
x = 4, y = 2
Step-by-step explanation:
Start by multiplying the first equation by 2:
2x + 2y = 12 --> 4x + 4y = 24
Subtract the second from the first:
4x + 4y = 24
- 5x + 4y = 28
4x - 5x = -x
4y = 4y = 0
24 - 28 = -4
so you end with -x + 0 = -4
Solve for x to get x = 4
Plug x = 4 back into 2x + 2y = 12 to find y.
2(4) + 2y = 12
8 + 2y = 12
2y = 4
y = 2
40,023,032 = (4 x 1000000000) + (0 x 100000000) + (0 x 10000000) + (0 x 1000000) + (2 x 100000) + (3 x 10000) + (0 x 1000) + (0 x 100) + (3 x 10) + (2 x 1)