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# AS-level S1 Statistics help!!! watch

1. Hey guys, i'm really stuck on this question on my homework

The weekly income, i , of 100 women workers was recorded.
the data were coded using y=(i-90)/100 and the following summations were obtained:
∑y=131, ∑y ²=176.84

Work out an estimate for the standard deviation of the actual women workers' weekly income.

If somebody could tell me how to do it and let me work it out for myself that'd be great
2. (Original post by jessica_anne_clu)
Hey guys, i'm really stuck on this question on my homework

The weekly income, i , of 100 women workers was recorded.
the data were coded using y=(i-90)/100 and the following summations were obtained:
∑y=131, ∑y ²=176.84

Work out an estimate for the standard deviation of the actual women workers' weekly income.

If somebody could tell me how to do it and let me work it out for myself that'd be great
Do you know the standard deviation formulas?
3. (Original post by jessica_anne_clu)
Hey guys, i'm really stuck on this question on my homework

The weekly income, i , of 100 women workers was recorded.
the data were coded using y=(i-90)/100 and the following summations were obtained:
∑y=131, ∑y ²=176.84

Work out an estimate for the standard deviation of the actual women workers' weekly income.

If somebody could tell me how to do it and let me work it out for myself that'd be great
Can you work out the s.d. of y from the information given?
4. (Original post by jessica_anne_clu)
Hey guys, i'm really stuck on this question on my homework

The weekly income, i , of 100 women workers was recorded.
the data were coded using y=(i-90)/100 and the following summations were obtained:
∑y=131, ∑y ²=176.84

Work out an estimate for the standard deviation of the actual women workers' weekly income.

If somebody could tell me how to do it and let me work it out for myself that'd be great
Well to explain firstly if the data is coded then the the deviation of the data wont change since each value has been manipulated equally by the coding, so sd is just using the formula for variance and then square rooting or Square root sum of y/n - ybar squared. ybar is = 131/100

so 176.84/100 - 131/100 ( all square rooted)

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