A snail covered 3mm in the frst sec and 4 mm each in each successive sec,for a certain number of sec.However if it had covered 1mm in the 1 st sec and 8 mm more in each successive sec for some secs, then the difference between the length of the path it would have covered during the same time and the actual path that it actually took would have been more than 6 mm but less than 30 mm.find the time for which the snail moved?

ans:3sec
in 1st condition in 2sec it will move for 7mm and in 3 sec 11mm
in 2nd condition in 2sec - 9mm and 3sec - 17mm
difference is 6mm condition is satisfied so that ans is 3sec
11 years agoHelpfull: Yes(10) No(14)
@ADITYA : even if u take 3 or 5 sec then also it will be more than 6 sec.
so how can u say that it is 4 sec only..??
11 years agoHelpfull: Yes(4) No(1)
ans is 3sec
1st condition 3sec 3+4+4=11
2nd condition 3sec 1+(1+8)+(9+8)=27
so ans =3sec
11 years agoHelpfull: Yes(2) No(7)
For 3 sec
1st condition - 11mm
2nd condition - 17mm
difference is 6mm
So answer is not 3sec

For 4 sec
1st condition - 15mm
2nd condition - 25mm
difference is 10mm
So it may be 4 second

For 5 sec
1st condition - 19mm
2nd condition - 33mm
difference is 14mm
So it may be 5 second

For 6 sec
1st condition - 23mm
2nd condition - 41mm
difference is 18mm
So it may be 6 second
10 years agoHelpfull: Yes(1) No(2)
1 4 4- in the first case=11mm in 3 sec
1 9 17- in the second case(8 mm more in each successive sec)=27 in 3 sec.
so the difference b/w their path=27-11=16 mm (greater than 6, less than 30) in 3 sec.
so the time taken is 3 sec..
9 years agoHelpfull: Yes(1) No(0)
ans -8 sec
becoz in 8th sec
31mm-1st condition
57 mm -2nd condition
difference betwwen them 57-31=26 WHICH IS LESS THAN 30MM AND MORE THAN 6MM so
the answer is 8 sec
10 years agoHelpfull: Yes(0) No(0)

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