Answer:
0.3431
Step-by-step explanation:
Here, it can work well to consider the seeds from the group of 18 that are NOT selected to be part of the group of 15 that are planted.
There are 18C3 = 816 ways to choose 3 seeds from 18 NOT to plant.
We are interested in the number of ways exactly one of the 10 parsley seeds can be chosen NOT to plant. For each of the 10C1 = 10 ways we can ignore exactly 1 parsley seed, there are also 8C2 = 28 ways to ignore two non-parsley seeds from the 8 that are non-parsley seeds.
That is, there are 10×28 = 280 ways to choose to ignore 1 parsley seed and 2 non-parsley seeds.
So, the probability of interest is 280/816 ≈ 0.3431.
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The notation nCk is used to represent the expression n!/(k!(n-k)!), the number of ways k objects can be chosen from a group of n. It can be pronounced "n choose k".
Putting it in simpler terms
Answer:Although the Quadratic Formula always works as a strategy to solve quadratic equations, for many problems it is not the most efficient method. Sometimes it is faster to factor or complete the square or even just "out-think" the problem. For each equation below, choose the method you think is most efficient to solve the equation and explain your reason. Note that you do not actually need to solve the equation. a. x2+7x−8=0x
2
+7x−8=0, b. (x+2)2=49(x+2)
2
=49, c. 5x2−x−7=05x
2
−x−7=0, d. x2+4x=−1x
2
+4x=−1.
Answer:
30
Step-by-step explanation:
2/9 and 5/6 have a lcm of 30.