Number of times pencils are more than rubbers = 7 ÷ 2 = 3.5 times
Answer: 3.5 times
Step 1a. For a card number with an even number of digits (e.g., Visa or MasterCard), double alternating digits starting with the first digit in the sequence.
Step 1b. For a card with an odd number of digits (e.g., American Express), double alternating digits starting with the second digit in the sequence.
Step 2. If the doubling resulted in a number with two digits, add them together to get a single digit number
Step 3. Now go back to the original credit number and replace the digits that you doubled with the new value — either the doubled value, or the doubled value with the digits added together — and add it all up.
Step 4. Check to see if the sum is evenly divisible by 10 (you can simply look to see whether or not it ends with a zero).
If the card number does not pass this check, then it is not a valid number. If, on the other hand, it does pass, then it may be a valid number with valid credit report.
Answer:
The solution of the system can be given as (5,-8).
Step-by-step explanation:
Given system of equations:
To solve the given system of equations:
Solution:
We will use substitution to solve the given system.
We will substitute the 
values in terms of 
from the equation into the other equation to solve for
Substituting into .
We have:
<em>Using distribution.</em>
<em>Combining like terms.</em>
Adding 6 both sides.
Dividing both sides by 3.
∴ 
<em>Plugging in into .</em>
We have,
∴ 
The solution of the system can be given as (5,-8).
Answer:
20 meters
Step-by-step explanation:
The shadow of the building will look like a right triangle. In this problem, the hypotenuse of the triangle is 25 meters, and one of the sides is 15 meters. What we are trying to find is the length of the other side.
We can do this by using pythagoreans theorem.
So, the last side (or the height of the building) is 20 meters.
