Answer:
Step-by-step explanation:
4x + y = 22
y = x - 3
4x + y + y = 22 + x - 3
4x + 2y = 19 + x
4x - x + 2y = 19 + x - x
3x + 2y ÷ 3 = 19 ÷ 3
For On call = 10/3.5 = $2.85 for per hour
For talk time 1.25/1/2= $2.5 for per hour
Answer:
4th choice which is 50.24 sq.m
Answer:
- digits used once: 12
- repeated digits: 128
Step-by-step explanation:
In order for a number to be divisible by 4, its last two digits must be divisible by 4. This will be the case if either of these conditions holds:
- the ones digit is an even multiple of 2, and the tens digit is even
- the ones digit is an odd multiple of 2, and the tens digit is odd.
We must count the ways these conditions can be met with the given digits.
__
Since we only have even numbers to work with, the ones digit must be an even multiple of 2: 4 or 8. (The tens digit cannot be odd.) The digits 4 and 8 comprise half of the available digits, so half of all possible numbers made from these digits will be divisible by 4.
<h3>digits used once</h3>
If the numbers must use each digit exactly once, there will be 4! = 24 of them. 24/2 = 12 of these 4-digit numbers will be divisible by 4.
<h3>repeated digits</h3>
Each of the four digits can have any of four values, so there will be 4^4 = 256 possible 4-digit numbers. Of these, 256/2 = 128 will be divisible by 4.
