Yes it's true!

How can this be?

let's take a look!

ok, first, look at this problem...

13 x 7 ----

now, multiply the three 7 times and place the result like this...

13 x 7 ----21

next, multiply the one 7 times and place the result like this...

13 x 7 ---- 217

add the 21 and 7...

13 x 7 ---- 21 + 7 ----28

and you get 28. therefore, 13x7=28.

WHAT? You want me to prove it by division? Well, here goes...

--- 7)28

now let's start with the 2.

--- 7)28

now, how many times does seven go into 2?

zero. you cannot divide 7 into 2.

so, you go to the 8.

--- 7)28

now, how many times does seven go into 8?

one. so, place the 1 like this...

1---- 7) 28

put the 7 under the 28 like this...

1 ---- 7) 287

and subtract the 7 from the 28...

1 ---- 7) 28 - 7 --21

next, how many times does 7 go into 21?

3. so you put the 3 to the right of the 1, put the product of 3x7 under the 21, and...

13---- 7) 28 - 7 -- 21 -21--0

you have no remainder, so the answer is an integer.

therefore, 7 into 28 is 13.

WHAT? You want me to prove it by addition? well, consider this...

13 + 13 + 13 + 13 + 13 + 13 + 13 ----

now, add the 3's together: 3. 6. 9. 12. 15. 18. 21.

13 + 13 + 13 + 13 + 13 + 13 + 13 ----21

... add the 1's: 22. 23. 24. 25. 26. 27. 28.

13 + 13 + 13 + 13 + 13 + 13 + 13 ---- 21 +7----28

there! that proves that...

d.t.

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