Answer:
easy = 391 items
hard = there are 8 more girls than there are boys
Answer:
Step-by-step explanation:
1/9
(1*4) / (9*4) = 4/36
(1*4) / (9*4) = 5/45
The first one is the ratio as it is stated in the problem.
The second one multiplies top and bottom by 4
The third one multiplies top and bottom of the top ratio by 5.
For i=1 ===> Sum=4
for i=2===> Sum=2
for I=3===> Sum=1
Hence the answer is 7
Or you could have use the Sum formula of a GP:
Sum = a(1-r)^n/(1-r), with a=1, r=1/2 & n=3