You've decided to give your best friend a bag of marbles for his birthday.
Since you know that your friend likes
green marbles better than red ones, the
bag has twice as many green marbles as
red.
The label on the bag says it contains a
total of 84 marbles.
How many green marbles are in the bag?

Green marbles = 56

Red marbles = 28

Step-by-step explanation:

let's assume the number of red marbles be x

then the number of green marbles = 2x

( since green marble is twice the red ones )

and we know,

green marbles + red marbles = total marbles

=》2x + x = 84

=》3x = 84

=》x = 84 / 3

=》x = 28

so, number of red marbles = x = 28

number of green marbles = 2x = 56

sorry i dont know my friend

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.