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What two 2-digit numbers add up to 100 and together contain a digit that is present three times?
Hint
If the numbers had to add up to 56, the answer would be 23 and 33. The 3 is present three times in these two numbers.Answer
45 and 55Hide Hint Show Hint Hide Answer Show Answer
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cougheasycough
argh!! i shoulda known thhat
yeah
its quite
easy.
not very
challenging
its quite
easy.
not very
challenging
Well, it was a little harder, before the editors put in the example line. In m opinion, the example gives away the riddle.
[a(10) + a] + [b(10) + a] = 100
b = [100 - [a(10) + a] - a]/10
b = (100 - 12a)/10
[a(10) + a] + [{(100 - 12a)/10}(10) + a] = 100
11a + [(100 - 12a)/10]*10 + a = 100
If a = 5, and b = 4, then all of those statement are true. I just can't actually solve for 'A'... Help please?
b = [100 - [a(10) + a] - a]/10
b = (100 - 12a)/10
[a(10) + a] + [{(100 - 12a)/10}(10) + a] = 100
11a + [(100 - 12a)/10]*10 + a = 100
If a = 5, and b = 4, then all of those statement are true. I just can't actually solve for 'A'... Help please?
Sane you dont need algebra for this. But even if you decide to use algebra (as you seem to be in love with it) here's how you proceed from your starting equation: reduce it to:
12a + 10b = 100, which again reduces to
6a + 5b = 50
Now since 5b is a multiple of 5, 6a also has to be a multiple of 5. so being a multiple of both 5 and 6 the only positive integral value for the term 6a is 30. which means a = 5. Substituting it back in the eqaution, you get b = 4
This, in my opinion is the only algebraic way to do it.If there's another, please let me know at [email protected]
12a + 10b = 100, which again reduces to
6a + 5b = 50
Now since 5b is a multiple of 5, 6a also has to be a multiple of 5. so being a multiple of both 5 and 6 the only positive integral value for the term 6a is 30. which means a = 5. Substituting it back in the eqaution, you get b = 4
This, in my opinion is the only algebraic way to do it.If there's another, please let me know at [email protected]
"Well, it was a little harder, before the editors put in the example line"
Huh? Why would someone add a hint to this? Isn't it easy enough already?
Huh? Why would someone add a hint to this? Isn't it easy enough already?
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