This video shows some shortcuts to finding out if a number is divisible by 2, 3, 4, 5, 6, 8, 9, and 10.

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If you click this in 2021 you're a legend.

Thanks

Translation in English

In India we study it in 3 class only

Abe india mein ye 3 class mein hi padha de te hain

Ye to tatti hai

its sooooo helpful some teachers make it all so komplikated

I came here for 49729

thank very nice

Eric plz pin this..

for 7: for example 1372

1372 take out ones digit and multiply by 2.

take 2*2 from 137

137-2*2 = 133 then take out 3 and multiply by 2.

take 3*2 from 13

13 – 3*2 = 7 seven is divisible by 7 so yes

1385:

1385 take out five, 5*2

138-5*2 = 128 take out 8, 8*2

12 – 16 = -4 oi not divisible by 7 lol

———————————————————————

EDIT ADDITION: for 11: 121

1st digit + 3rd digit = 2

2nd digit = 2

2 – 2 = 0 divisible by 11

1331

1st digit + 3rd digit = 4

2nd digit + 4th digit = 4

4-4 = 0

3267

1st dig + 3rd dig = 9

2nd dig + 4th dig = 9

9-9 = 0 yay

19415

1st dig + 3rd + 5th = 10

2nd + 4th = 10

10 – 10 = 0 u get the point

19526

1st + 3rd + 5th = 12

2nd + 4th = 11

12 – 11 = 1 not divisible by 11

194206

1st + 3rd + 5th = 1 + 4 + 0 = 5

2nd + 4th + 6th = 9+2+6 = 17

17 – 5 = 12 not divisible by 11

179762

1st + 3rd + 5th = 1 + 9 + 6 = 16

2nd + 4th + 6th = 7 + 7 + 2 = 16

16 – 16 = 0 yay

—————————————————————

for 13: example 12480

12480 take out 0, 0*9

1248 – 0*2 = 1248 take out 8*9

124 – 8*9 = 52 take out 2, 2*9

5 – 2*9 = -13 divisible by 13

6121 take out 1, 1*9

612-9 = 603 take out 3, 3*9

60-3*9 = 33 take out 3, 3*9

3 – 3*9 = -24 no divisible check: 4*9

-2-36 = -38 still not divisible…

ok you understand?

Oh so… I'm so late to comment, but the same rule that applies for 6 applies for 8, except using 2 and 4. What I usually say is that if both 2 & 3 are factors, so is 6. And if 2 & 4 are factors, so is 8.

came for the 7….

super bro…..

please make video on 11-20. div…..

Thank you soooo much we are doing this in school my teacher was really impressed when I told her the tricks

Thanks so much

thank you so much

I came here for the 7

THANK YOU VERY MUCH 🙂 <3

its help full for me thanks sir

Thank you so much.

Very Helpful

Really good job