Question

http://prntscr.com/1nbd5n

Answer 1

@terenzreignz @ganeshie8 @dan815

Answer 2

I was just trying randomly :P
--------------------------------
Let total number of human beings be H
Total number of human feets=>2H
1/10 H lost their feet
Remaining feets: 2H-1/10H =>199/10 H
Let total number of dogs be D
Number of dog feets=>4D

Answer 3

Should \(\LARGE 4D+\frac{199H}{10}=77?\)

Answer 4

youi mean, \(\LARGE 4D+\frac{\color{Red}{19}H}{10}=77?\)

Answer 5

oh yea sorry :D

Answer 6

\[\large 40D+19H=770\]

Answer 7

then it looks right, but since we have two variables H, D.. and oly one equation, its going to be tricky

Answer 8

lets use this, H and D can be oly integers

Answer 9

options are 4,5,6
we can make use of it anyhow?

Answer 10

diophantine equation?

Answer 11

oh we;re given options ? then its easy
plug each one, and see which one gives integer for other variable

Answer 12

but then what about H

Answer 13

lets try

Answer 14

H=4, D= ?
H=5, D=?
H=6, D= ?

Answer 15

40D+19H-770=0
-----------------
D=4
19H=610
H=32.10 so no.
--------------------

Answer 16

40D+19H-770=0
-----------------
D=4
19H=610
H=32.10 so no.
--------------------
D=5
19H=770-200
19H=570
H=30 seems correct?

Answer 17

yes D=5 works

Answer 18

what if 2 options gave integral values? hmm..

Answer 19

good q, have to think

Answer 20

think overnight and let me know :P

Answer 21

il try im all low on my capacities today..

Answer 22

okay !

Answer 23

lets find other integer solutions of H and D for equation
40D + 19H = 770

Answer 24

we need to bother oly about solutions in range : 0 < H,D < 77

Answer 25

also we have :-
(770-40D) | 19
(770-19H) | 40

Answer 26

(770-40D)|19

770/40 = 19.25, that means oly 19 possible positive real values for H, when D is an integer.

Answer 27

cool :O

Answer 28

m just putting somthing.. lol

Answer 29

il do the donkey method from here i think, il test all 20 values and see

Answer 30

lol

Answer 31

```
H D
38.4210526315789 1
36.3157894736842 2
34.2105263157895 3
32.1052631578947 4
30 5
27.8947368421053 6
25.7894736842105 7
23.6842105263158 8
21.5789473684211 9
19.4736842105263 10
17.3684210526316 11
15.2631578947368 12
13.1578947368421 13
11.0526315789474 14
8.94736842105263 15
6.84210526315789 16
4.73684210526316 17
2.63157894736842 18
0.526315789473684 19

```

Answer 32

awww man

Answer 33

thats not useful for me... see if u can identify a pattern somthing... or u were saying about diophontine equations... you did course on number theory ?

Answer 34

nah only heard of it on OS only :P

Answer 35

ohk...:) reminds me @mukushla tutorial on diophantine equaitons.. thats the first time i got in touch wid them

Answer 36

he may give some cool number theory proof for this when he gets ol