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