Posted by Shawna Lynn on Monday, April 29, 2013 at 2:33pm.
Solve the mathematical puzzle.
Determine the digits of R from these clues.
The first digit is the answer when the third digit is divided by 2.
The second and third digits add to 7.
The second digit minus the first digit is 1.
R is a three-digit number: ____
I have never understood how to do this.
- Math - Steve, Monday, April 29, 2013 at 2:50pm
Call the digits a,b,c left-to-right
a = c/2
b+c = 7
b-a = 1
we see that c=2a, so
subtract to get
Thus c=4 and b=3
Or, just working with the specs,
c must be even, since it can be divided by 2. So, R is one of the forms
Since the last two add to 7, R must be
Answer this Question
More Related Questions
- Math - Determine the digits of Y from these clues. The digits of Y add to 18. ...
- math - Find the four-digit number described by these three clues. 1) The first ...
- Math - R is a 3 digit number The first digit is the answer when the third digit ...
- math - Solve the mathematical puzzle. Determine the digits of F from these clues...
- math - this code has five digit 1,2,3,4,5. the first digit plus the second digit...
- math - Find a six-digit even number containing no zeros and no repeating digits ...
- math - it is a 3 digit number all the digits are different the first and second ...
- Math - A number has four digits. the sum of the first and last digits is twice ...
- Math - i am a four digit number. all of my digits are different. my first digit ...
- Math - A number has 4 digits. The sum of the first and last digit is twice the ...