Expert: Ahmed Salami - 10/21/2004

Question
Thank you for your answer, and I hope you're feeling better now.

One question: what does that mean by "the units digit"? Can you paraphrase it?
   

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Followup To
Question -
Hello Ahmed,

I'd appreciate if you could show me the operation to solve the following question.

"For a given two-digit positive integer, the tens digit is 5 greater than the units digit. The sum of the digits is 11. Find the integer."

Thanks and regards,

Ang-sui


Answer -
Hi Ang-Sui,
I'm sorry for the delay, i was a bit ill.
If the first and second digits are x and y respectively, then according to the information given
x - y = 5
x + y = 11
Adding both equations to eliminate y gives
2x = 16
x = 8
but y = x - 5
     = 8 - 5 = 3
The value of the integer is 10x + y
= 10(8) + 3
= 80 + 3
= 83
Regards.

Answer
Hi Ang-Sui,
I feel better now, thank you.
'the units digit' simply refers to the last number to the right of a whole number. This is said in regards to its place value which is one. To make this more understandable, consider the number 283. This number can be written as
283 = 2(100)+ 8(10)+ 3(1)
Looking at this, you'll understand what place values are. So, we can say that 3 is the units digit, 8 is the tens digit and 2 is the hundreds digit.
I hope you can now figure it out.
Regards.