Solve without using calculator?

Question

Solve without using calculator?

Answer 1

6.1710

Answer 2

1909217123713637812347892347923423984723489234734301248123490247230489723049823904720394247 in the set of imaginary numbers[to know what they are, ask your math teacher or consult a decent book.]

Answer 3

6.17

Answer 4

sounds stupid... some corny fraction comes 6.17... that too with a calculator!.... howd u do without?...id like to know pleeeseee....

Answer 5

I love the answers "i can see that it tends to 2".



Considering each term towards the end adds almost 1 extra each time (7/8 +/- = 8/9 +/- = 1 ) either they are still on acid, or a mercian.



i imagine the 6.17 people are correct.

Answer 6

You haven't made the question quite clear enough.



Without a calculator I can see that the series tends towards 2.



However you haven't indicated whether it is intended to be a continuing series, so I had to use a spreadhseet to get the answer after 9 terms (1.76388888...)

The answer after 100 terms would be 1.98009901.



6.17... is also a valid answer. It can be got by finding a common denominator [504] for all of the fractions, then finding the sum. I wasn't able to do that without a calculator though!

Answer 7

6.18

Answer 8

6.17

Answer 9

6.17

Answer 10

I'd start by pairing them up a bit to simplify common denominators.

0/1 = 0

1/2+3/4+7/8 = 4/8+6/8+7/8 = 17/8

2/3+5/6+8/9 = 12/18+15/18+16/18 = 43/18

4/5+6/7 = 28/35+30/35 = 58/35



Now there's only 3 fractions, 58/35+43/18+17/8. Time to find the grand common denominator. I'm using underscores to indent since spaces get stripped out.

_35

x18

- - -

280

35

- - -

630



_630

x__8

- - - -

5040



But since 2 will go into 630 and 8, we can reduce that by half, 2520.

Now, find the multipliers we want through long division to use against the numerators.



_____72

35 | 2520

___245

___- - -

____070

_____70

_____- -

______0





____140

18 | 2520

___18

___- -

___072

____72

____- -

____000...



This is too tedious after all. Guess I'll keep going, but I'm going to use my calculator a little, now.



2520/35=72

2520/18=140

2520/8=315



58/35+43/18+17/8 =

4176/2520+6020/2520+5355/2520 =

15551/2520



And that's my final answer. What do I win?

Answer 11

hi sin 2a = 2 sin a cos a sin 30 = 2 cos 15 sin 15 = 1/2 = 0.5 regards

Answer 12

If its an infinite series,it diverges;but if only upto 8/9,thn what these ppl say is correct.

Answer 13

403/72

Answer 14

You need a slide rule.

Answer 15

I don't know I failed math



I know what you’re trying to do, you’re trying to give me a headache aren’t chya.....aren’t chya.....I never liked you, headache giver

Answer 16

I know i know its 2 right? lol

Answer 17

6.17

Answer 18

four