Answer:
C.
Step-by-step explanation:
You are multiplying $7 by c calculators.
The answer is SR=3
2x+23+x+21=14
Solve for x you get
x=-10
Substitute x
2(-10)+23=3
For this problem,we use the Fundamental Counting Principle. You know that there are 7 digits in a number. In this principle, you have to multiply the possible numbers for every digit. If the first number cannot be zero, then there are 9 possible numbers. So, the value for the first digit is 9. The second digit could be any number but less of 1 because it was used in the 1st digit. So, that would be 10 - 1 = 9. The third digit must be the value in the second digit less than 1. That would be 9 - 1 = 8. And so on and so forth. The solution would be:
9×9×8×7×6×5×4 = 544,320 7-digit numbers
1. i think 5 to 9
2. i think 3/8
3. 2.24
4. 164+3.28
hope this helps!