Hi all. I am doing revision for Elementary and Additional Mathematics and need help with the following question for my elementary mathematics GCSE O Level.

Thank you.

I hope someone is able to help me with the following questions. Thank you very much

1) Find the next two value of the sequence

7/8 , 2/3 , 1/2 , 4/11 , 1/4

I can't figure out any formula for this.

I tried using the arithmetic and geometric sequences and series, but I still can't find it.

2) A data has the following value,a, b, c,4 and 8. The mean fora, b, and c,is 8

the standard deviation fora b and cis sqrt(7)

find the standard deviation for the 5 values.

I did up till (a-8)^{2}+ (b-8)^{2}+ (c-8)^{2}= 21

I found the mean for the 5 values is 7.2.

Thank you for reading and the help!