We can solve this by setting up 2 equations. We can use any letters like. For now, I'll use x and y. So now we know that x - y = 0.7 and x + y = 1. Now we can eliminate one of the letters by adding or subtracting one equation from the other. I am going to eliminate y by adding the two together (the y and the -y cancel). This gives us 2x = 1.7, and so x = 1.7 ÷ 2 = 0.85 Finally, we can substitute x for 0.85 back into one of the original equations to figure out what y equals. I'm going to use x + y = 1. So now we have 0.85 + y = 1, so y = 1 - 0.85 = 0.15
The numbers, therefore, are 0.85 and 0.15 (you can check by using the other equation).
Theoretical Probability: she will pick the red pen 4-5 times in the 14 days (14days/3options=4.667times picked over the duration of the time allotted).
Experimental Probability: she picks the red pen 6/14 times
So the experimental is 1-2 times more than predicted via theoretical probability
Since we know that Sarah drives at 55 mph we can divide 1625/55 and get 29.45454... and I assume that they want it rounded so it will be around 29.5 hours
