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A cyclist accelerates at a steady rate from 38.4 kph to 49.6 kph in 8 seconds. How fast he riding 3.5 seconds after he starts to accelerate?

(A)44.7 km/h

(B)41.6 km/h

(C)39.8 km/h

(D)43.3 km/h

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He will be riding at 43.4 k/h after 3.5 seconds. This is because we first need to get the difference after 8 seconds, which is 11.4 k/h. 3.5 seconds after he starts accelerating he will have added 4.98 k/h which is the same as 5 k/h. You then add this to 38.4 k/h to get 43.4 k/p.

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Thank you very much :) I got it
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Cheater -_- but D haha too easy man

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I know, but Idk why I am getting 4.9 -_- I forgot this sh*t
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Just remind me the formula, isn't it

a=(v2-v1)/t ?
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Haha would you like for me to explain? I can if you want?
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Yes, I would appreciate that :)
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Ok so it took him 8 seconds to go from 38.4 to 49.6 so what you can do is find out his acceleration within that 8 seconds so you do 49.6-38.4 which equals 11.2 and so he can accelerate from 0 to 11.2 in 8 seconds so you take the 11.2 and divide it by 8 which is 1.4 so that means he can go 1.4 in 1 second so then you take 1.4 and times it by 3.5 and it gives you 4.9 so then you know that he can go from 0 to 4.9 in 3.5 seconds so then you add that to 38.4 and you get 43.3 kp/h ... Wait did you mean kp/h in the answer choices?
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Yes, that's Kilometers per hour. Thank you too, I got it when NYudeszzz said " You then add this to 38.4 k/h to get 43.4 k/p." , I also got 4.9 but didn't add it to 38.4.

Thank you :)
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Btw, I knew the formula all along, it's just that "after he starts to accelerate?" really tricked me -_-
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Hahaha alright great!
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