Anonymous

# Can you prove that 7 times 13 equals 28?

There are three ways to do it - one using addition, one using subtraction, and one using multiplication!

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• samk
Lv 4

Classic Abbott and Costello. Too old for most readers here.

http://joe-ks.com/archives_aug2005/Math_Proof.htm

• 4 years ago

7 Times 13

• Anonymous
6 years ago

How about division....28/7....7 into 2...7 will not go into 2...there is no way you will fit that big 7 into that little 2..so we take the 2 out for a minute cause we don't want to hurt the 2...now 7 into 8, 7 CAN go into 8, it goes in 1 time so now we do 1 x 7=7 now.....now we just had a 2 a minute ago, or a few seconds ago depending on how fast your reading this comment...28 - 7 = 21 and 7 goes into 21 3 times and BINGO...put the 3 to the right of the 1 and you got 13

7 times (1+3) is 28.

YES! How come? Because this is from an old episode of Abbott and Costello. In that episode, they were behind in their rent and tried to low-ball how much they owe by using this little trick.

(1) 7 x 3 = 21.

(2) 7 x 1 = 7

(3) 21 + 7 = 28.

FYI, in the episode, they also took 13 and added it 7 times as a double-check that 28 is the right answer. Won't tell you though how they got this one, but it's pretty interesting. In fact, I've used it in my business math class as an interesting little tidbit and to peak student interest.

• Anonymous
5 years ago

RE:

Can you prove that 7 times 13 equals 28?

There are three ways to do it - one using addition, one using subtraction, and one using multiplication!

Source(s): prove 7 times 13 equals 28: https://biturl.im/QdG2L

No. I've seen problems like this one before where the equation holds because the numbers are all in different bases (you have to determine the bases to prove them), but I can tell you without any calculations why it is impossible for this to be one of those problems. First, 7 and 13 are odd numbers in any base that they can be in, and that product must be odd. Because 28 is even (regardless of the base), the equation cannot hold.

Not only is this not one of those problems I described above, but it is impossible for that equation to hold in any case. I think you are leaving out some detail, or you misunderstood the problem, or did not type it correctly or something. Good luck!

• Anonymous

13 n 7 equals 28??

ok

lets seee...

3+1= 4

4 x 7=28

gocha!!

• 6 years ago

13

13

13

13

13

13

13

Apparently not without some kind of trick that doesn't constitute a valid mathematical proof. That is, not without breaking some mathematical rules in the process.

But I can certainly prove that (7 x 13) = 85 and also that (7 x 13) = 115 without conflict or violating any of the rules of formal mathematics.

Several other accurate answers exist also without violating any mathematical laws.