The probability that it will rain today is 50%. the probability that it will rain tomorrow is 40%. assuming today and tomorrow’s precipitation outcomes are independent from one another, what is the percent probability that it will rain on at least one of the two days? express your answer as a whole number.

Consider this option:
1. if suppose, that probability for the rain today is p=0.5, for tomorrow p1=0.4. Then probability for no rain today is q=1-p=0.5, for tomorrow is q1=1-p1=0.6.
2. According to the condition full probability is:
P=p*q1 + p1*q + p*p1=0.5*0.6+0.4*0.5+0.5*0.4=0.3+0.2+0.2=0.7 or 70%.

Note that: p*q1 means 'rain today, no rain tomorrow'; p1*q means 'no rain today, rain tomorrow' and p*p1 means 'rain today, rain tomorrow'.

Answer: choice c and choice d

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explanation

the graph has a slope of 1/3 because each time you move up 1, you go to the right 3. so, slope = rise/run = 1/3. we can cross choice a off the list since we want a slope of 3, rather than 1/3.

the first table shown has a slope of -3. this is because the rise is -6 and the run is 2, so slope = rise/run = -6/2 = -3. note how x increases by 2 each time (run) and y drops by 6 each time (rise). choice b can be eliminated.

the second table has a slope of 3. each time x goes up by 1, the y values increase by 3. slope = rise/run = 3/1 = 3. alternatively you can use the slope formula to prove that the slope is 3 here. use any two rows of values to generate the two points. choice c is one of the answers

the third table also has a slope of 3. let's use the slope formula to prove as such. i'm going to use the first two rows of the table. so i'll use the two points (2,1) and (5,10)

m = slope

m = (y2-y1)/(x2-x1)

m = (10-1)/(5-2)

m = 9/3

m = 3 so we get a slope of 3

choice d is the other answer

The answer is 109 times per second