Short cuts for Number Crunchers

[NoMathWhiz]

I have studied many of the back page questions and I am aware of many of the short cuts available for the number crunchers. Can anyone help me with a short cut for the following questions?

12B - 64 1/(0.79) + 1/(3(0.79)^3) + 1/(5(0.79)^5) + 1/(7(0.79)^7) = 3.34

12F - 64 1/(0.8) + 1/(3(0.8)^3) + 1/(5(0.8)^5) + 1/(7(0.8)^7) = 3.19

Any help would be greatly appreciated. I have already looked through Taylor Series to help, but couldn't find anything.

[88bobcat]

[BlasianAsian]

Heh. I see what you did there. But it takes about 30 seconds total to do those problems the normal way, so....

[88bobcat]

[BlasianAsian]

So you do it by drilling. I drilled. For a long time. And there we go.

There is no short-cut for these problems. That's why, like number sense, I'm practicing. Some things can only be done by rote memorization and practice. And that's what I'm doing. What else is there to it?

[nsguy1350]

Well, if you have an HP calculator (specifically HP32Sii works, I believe the same for the 33, and probably many other calculators as well) I would store the repeated number and then re-use it to speed up some.
I store the number as the letter right above the RCL key, so I can double-tap RCL to recall the number.
HP notation:
[.79][STO][RCL (storing as H I believe, so now to recall you double-tap)] then do your operation, and everytime you need that number, just recall. Not really a trick, but shaves off a bit of time.

[NoMathWhiz]

Thanks everyone for your replies. This really helped.

[sxk1693]

Can you guys tell me your NC speed?

I can usually do them around 8:00(average sometimes 7:30 sometimes 8:30) usually missing 1-3

[sxk1693]

I want to see if that is good enough or if I need to get faster.
I know nsguy usually does 7:00 with 0-2 misses and sometimes(usually) 6:00 with 5-8 mistakes...

[101dalmatians]

Ideal speed is 9 min.
That gives 21 min to do stated and its easy to do it in that time...
Once you start speeding up and gettin to 6min NCs, you are very likely to miss a lot
Now, I finish ncs in 9min. It used to be like 10-11 but now its decreased...
And try to get accuracy cuz w/out NC accuracy, ull **************************EPICLY FAIL A CALC TEST*************************************
The thing is on some NCs, I miss them by like 0.07 or 0.1 which is kinda stupid
I mean even if you put one number wrong in ur calc by one digit, your ans is gonna be different and wont be like within one sig fig unless ur lucky...

[101dalmatians]

[nsguy1350]

[BlasianAsian]

7 min with just number crunchers? Are you God?

[101dalmatians]

[BlasianAsian]

[007math]

[BlasianAsian]