Step-by-step explanation:
Note that t = d/r where t is time, d is distance, and r is rate/speed.
We can come up with two equations with the information given and the equation:
t_1 hr = (10 km)/(x km/hr)
t_2 hr = (12 km)/(x - 1 km/hr)
<em>where t_1 is the time taken to run the 10km the first day and t_2 is the time taken to run the 12km the second day.</em>
We know that 30 minutes is 1/2 of an hour and that t_1 is 30 minutes less than t_2 (as stated in the question). Therefore, we can write:
t_1 = t_2 - 1/2
Substituting the values we derived:
(10 km)/(x km/hr) = (12 km)/(x - 1 km/hr) -1/2
Then we can evaluate by multiplying by 2x(x-1) on both sides:
20(x-1) = 24x - (x)(x-1)
20x - 20 = 24x - x^2 + x
x^2 -5x -20 = 0
And we are done.
I hope this helps! :)
Oof, this is surely a tough one. But, if I'm looking at this correctly, than I think you were in the right mindset when trying to figure both of them out. Like, for #18, think about the formula; P(B|A) = P(A and B)/P(A). So, based on the question, you can let not rolling a 1 on the blue cube be A, and rolling a 1 on the red cube be B. Now, personally, I prefer using the decimals when heading into the equations, but I'll convert the product into a fraction for the instruction's sake. 0.02777777778 + 0.13888888889 = 1/6. 1/6 ≈ 17.7%. You can do the same for #19, the overall outcome would be 5/6, which would be about 83%. Now, that's just me really attempting my hand at it, I will say, Math is far from my strong suite. But, in all honesty, I really am doing my best to help (and no, it's not because of what you offered, lol, more rather I want to help people who struggle with the same problems I do). Anyways, I hope this helps, and if you need more information, or anything, just let me know! Wish ya the best of luck!! ^u^
Answer:M(-0,5;0)
Step-by-step explanation:
The answer is $1.25 a large drink
Because 17.5 - 12.5 = 5 / 4 = $1.25
I hope this helps