a, b, c, d are positive integers. If a/b has a remainder of 9 and c/d has a remainder of 10, what is the minimum possible value of b*d?
Answer key says 110.. I disagree, can someone explain why the following is not true:
If a = 1, c = 1
b = 9, d = 10 for an answer of 90.
1/9 = remainder of 9
1/10 = remainder of 10
Why, "the remainder must always be smaller than the divisor"? If the numerator is smaller than the divisor, doesn't the divisor = the remainder?
Minimum Divisor for Remainder Problem
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The problem is above, in green.ShaneK wrote:a, b, c, d are positive integers. If a/b has a remainder of 9 and c/d has a remainder of 10, what is the minimum possible value of b*d?
Answer key says 110.. I disagree, can someone explain why the following is not true:
If a = 1, c = 1
b = 9, d = 10 for an answer of 90.
1/9 = remainder of 9
1/10 = remainder of 10
Why, "the remainder must always be smaller than the divisor"? If the numerator is smaller than the divisor, doesn't the divisor = the remainder?
1 divided by 9 equals 0 with remainder 1 (not 9)
1 divided by 10 equals 0 with remainder 1 (not 10)
Cheers,
Brent
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If a=9 and b=10, then a divided by b = 0 with remainder 9.ShaneK wrote:a, b, c, d are positive integers. If a/b has a remainder of 9 and c/d has a remainder of 10, what is the minimum possible value of b*d?
If c=10 and d=11, then c divided by d = 0 with remainder 10.
So, bd = (10)(11) = 110
Cheers,
Brent
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That's an easy (and common) mistake to make.
The best thing is that you made it before test day.
Cheers,
Brent
The best thing is that you made it before test day.
Cheers,
Brent