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- Video Course
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- General GMAT Strategies - 7 videos (all free)
- Data Sufficiency - 16 videos (all free)
- Arithmetic - 38 videos (some free)
- Powers and Roots - 36 videos (some free)
- Algebra and Equation Solving - 73 videos (some free)
- Word Problems - 48 videos (some free)
- Geometry - 42 videos (some free)
- Integer Properties - 38 videos (some free)
- Statistics - 20 videos (some free)
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- Analytical Writing Assessment - 5 videos (all free)
- Reading Comprehension - 10 videos (all free)
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- Integrated Reasoning - 17 videos (some free)

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## Comment on

Integer Properties Strategies## Brent,

Could you help with the Exercise #161 of OG17?

Thanks,

Pedro

## Glad to help!

Glad to help!

Here's my step-by-step solution: https://gmatclub.com/forum/club-x-has-more-than-10-but-fewer-than-40-mem...

Cheers,

Brent

## Brent,

Thank you!

Cheers,

Pedro

## why is 51 not a prime number?

## 51 = 3 x 17

51 = 3 x 17

The sum of the digits = 5 + 1 = 6

Since 6 is divisible by 3, we know that 51 is divisible by 3

Cheers,

Brent

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