Arithmatic tips or excercises?

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justhanging

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I keep getting tripped up on MCAT arithmetic. I spend to much time working out the math and keep getting wrong answers just because I did the calculations wrong. Anyone else had a problem like this? Any tips or suggestions would be appreciated.

sample calculation I did wrong:

x = (.7 * 12)/5

Am good at math but my arithmetic is horrible and I don't know my multiplication tables well.

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Those tips are good, but I would still memorize the multiplication table (up to 12). I can't find 8.4/5 off the top of my head, but I can do .7*12=(7*10)+14 and move over decimal point, then estimate from there. make flashcards or something, but it shouldn't take too long since people learn it in elementary school.
 
Those tips are good, but I would still memorize the multiplication table (up to 12). I can't find 8.4/5 off the top of my head, but I can do .7*12=(7*10)+14 and move over decimal point, then estimate from there. make flashcards or something, but it shouldn't take too long since people learn it in elementary school.

You would think that it doesn't take long but it does. When memorizing the multiplication table you are just memorizing numbers with no significance behind it. Ive spent a lot of time trying to memorize it and it still doesn't stick. I think children's brains are more receptive to that kind of memorization.
 
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I keep getting tripped up on MCAT arithmetic. I spend to much time working out the math and keep getting wrong answers just because I did the calculations wrong. Anyone else had a problem like this? Any tips or suggestions would be appreciated.

sample calculation I did wrong:

x = (.7 * 12)/5

Am good at math but my arithmetic is horrible and I don't know my multiplication tables well.

I think it's very helpful to remember fractions 1/2 to 1/10.

For this problem, I would of multiplied 7 x 12 = 84 (move the decimal back 1),
so 84 --> 8.4

Dividing by 5 is the same thing as multiplying by 1/5. The fraction of 1/5 is 0.2 so 8.4 x 2 = 16.8 (move the decimal back 1) and you get 1.68

I think with practice, this type of math becomes easier.
 
This isn't even a tip. This requires just plain exercise. There's fluency charts for your multiplication tables, division tables, addition, and subtraction from 1-9 with cumulative exercises. You really should be able to get 1.68... at least in a couple seconds.

how is it no significance? You learn the whole 8 x 3 as in 8 baskets with 3 apples in it each. You kind of need to know this stuff. By the time you're in college, it's not even basic math.You're hardly far off a child's age... it's still pretty young, but just a little harder. get started. doing things in your brain fast will just save time instead of punching it in a calculator. Talk about mindless..it's punching stuff in the calculator for 8.4/5.

try to start with just 1 digits from 1-9, then 2 digits from 1-9, and then 3 digits. By then, you should be quick enough to just do every calculation and then you just stick your decimal point to however many places. you shouldn't round a question like 8.4/5. There might be another option that was 8.6/5. It's 3 sig figs which is pretty standard.

also, for scientific notation questions, just make sure you are setting yourself with the same format. change it to 1-9 x 10 ^. Do the scientific notation first then the numbers.

For conversions, if you have a question with 698 nm, just do it in your head as 698 x 10^-9 first instead of trying to converting to m first as 6.98^10-7.

With 1/n + 1/n^2 questions, just think of the inverse first then inverse again.

whatever you do, make sure you're consistent. since you say you're good at math, i'm sure you know this, but keep every method the same. everything is just about practicing a certain mold and fitting everything into nearly the same form and solving for something whether it's math or science or whatever. for me, i've practiced so much more with fractions that it's easier, but with practice, all the calculations come out quickly anyways. just work hard.
 
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