# Assignment 7 - STEP question : minor mistake ?

Hello everybody !

It seems to me there is a minor in STEP I assignment 7 STEP question solution.

In the solution, it's said : "You can then use (k(1) + 1) (k(2) + 1) (k(3) + 1) (k(4) + 1) = 1323 to eliminate everything but three values (the three solution values, 2; 6 and 8). However, I think -4 is also a possible value since -4 | 576; (-4 - 1) | 173; and (-4 + 1) | 1323.

Personally, while answering this question I ended with 4 possible values : -4; 2; 6 and 8 and I then had to underline that we could either have 2; 6; 6; 8 or -4; -4; 6; 6 as values of k(1); k(2); k(3) and k(4) so that their product would equal 576.
I then showed that only the first case did not contradict the (...) = 175 equation.

Am I wrong ?

Anyway, thanks for this website - it's really helpful to prepare !

### That sounds right to me

This assignment has been though several updates, and each time we have found new "possible solutions" that we should have included. We'll take another look at it.

Thanks!

### Thanks

No problem, and thank you for the quick answer !

### Possible values of k_1

I agree with your 4 values of $k_1$ (2, 6, -4, 8). I am editing the hints now.

### Thank you

Thank you

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