Answer:
She had a total of 80 throws.
Step-by-step explanation:
4x20 (20x5%=100%) = 80, so she had 80 throws.
Let R and B be the number of red and blue marbles respectively.
Then,
R+B = 36
R:B = 5:4
Therefore,
Ratio of red marbles = 5/9
Ratio of blue marbles = 4/9
This means,
R = 5/9*36 = 20 marbles
B = 4/9*36 = 16 marbles
If one blue marble is removed from the bag, the new B= 16-1 = 15 blue marbles and the new total of marbles in the bag = 36-1 = 35 marbles.
The new ratios are
R = 20/35 =4/7
B = 15/35 = 3/7
That is, R:B = 4:3
The reasoning of the student is wrong. When a marble is removed, both the number of blue marbles changes as well as the total of the marbles in the bag. In other words, both the values in the ratio reduce by 1.
Answer:
Hey there!
There are a total of 20 children, and 2+6, or 8 are girls.
Thus the probability of choosing a girl is 8/20, or 2/5.
There are 2 left handed girls, so the probability is 2/20, or 1/10.
Hope this helps :)