Answer:
They practiced a total of 75 math facts in all!
60 + 15 = 75 :D
24+15+11=50, the total number of times the markers were chosen.
Since 11 of these 50 tries resulted in a red and blue marker, the probability is 11/50. This is equal to 0.22 or 22%.
The original price was 725.
Explanation:
"36% less than" means taking 36% away from 100%. 100-36 is 64, so 64% remains when 36% is taken away. So, 64% of the original table's price is 464.
So, if the original price was x, 464=0.64x
Solve this by dividing both sides by 0,64:
725=x
So, the original price was 725.
Answer:
The formula to calculate standard deviation from probability is \sqrt(n*p*(1-p)). n is the sample size, and 200 in this case (number of putts for practice). p is 80% or 0.8, the probability that he can make it. So the standard deviation is \sqrt(200*0.8*(1-0.8)=\sqrt(200*0.8*0.2)=\sqrt(16)=4.
9 times 5 is 45
6 times 5 is 30
Difference is 15
