Answer:
7.4 x (87-24)
Step-by-step explanation:
The translation is that you multiply the difference of two numbers. So you must get the difference first, that's why you put parenthesis around 87-24. Your answers are sideways and are hard to read, so I'll just give you the correct answer without the answer choice.
<h3>
Answer: 375</h3>
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Work Shown:
a = 300 = first term
r = 60/300 = 0.2 = common ratio
We multiply each term by 0.2, aka 1/5, to get the next term.
Since -1 < r < 1 is true, we can use the infinite geometric sum formula below
S = a/(1-r)
S = 300/(1-0.2)
S = 300/0.8
S = 375
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As a sort of "check", we can add up partial sums like so
- 300+60 = 360
- 300+60+12 = 360+12 = 372
- 300+60+12+2.4 = 372+2.4 = 374.4
- 300+60+12+2.4+0.48 = 374.4+0.48 = 374.88
and so on. The idea is that each time we add on a new term, we should be getting closer and closer to 375. I put "check" in quotation marks because it's probably not the rigorous of checks possible. But it may give a good idea of what's going on.
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Side note: If the common ratio r was either r < -1 or r > 1, then the terms we add on would get larger and larger. This would mean we don't approach a single finite value with the infinite sum.
Step-by-step explanation:
Circumference of wheel = πd = 0.75πm.
How far the car travels per minute
= 60s * (14m/s) = 840m.
Hence number of revolutions per minute
= 840m / 0.75πm
= 356.507....
= 357. (nearest whole number)
1 5/8
Trust me :)
If it's wrong then sue me instead :D
