Logical Reasoning - Number Series - Discussion
Discussion Forum : Number Series - Type 4 (Q.No. 2)
Directions to Solve
Find the number that fits somewhere into the middle of the series. Some of the items involve both numbers and letters
2.
Look at this series: 664, 332, 340, 170, ____, 89, ... What number should fill the blank?
Answer: Option
Explanation:
This is an alternating division and addition series: First, divide by 2, and then add 8.
Discussion:
32 comments Page 3 of 4.
Mihir said:
1 decade ago
1> 664/2 = 332-> 2nd number.
2> 340/2 = 170-> 4th number.
3> 89*2 = 178 (5th no) == 178/2 = 89-->6th no.
2> 340/2 = 170-> 4th number.
3> 89*2 = 178 (5th no) == 178/2 = 89-->6th no.
Karamat subhani said:
1 decade ago
If 664/340 = 1.952.
Similarly 332/170 = 1.952.
And then 340/178 = 1.952.
In this way ratio will be same and so we can say 178 is correct answer.
Similarly 332/170 = 1.952.
And then 340/178 = 1.952.
In this way ratio will be same and so we can say 178 is correct answer.
Neetu said:
1 decade ago
I agree with kenneth we have to look form both the ends from reverse way we can see the previous no. of last the no. will be the double of it.
Kenneth Tombing said:
1 decade ago
The pattern is reversed in this case. Its easy if calculated from the end.
Rahul said:
1 decade ago
170*2=340
332*2=664
so
89*2=178 ans
332*2=664
so
89*2=178 ans
Reet said:
1 decade ago
I think i can find a easier way..
664-332=332
340-170=170
So in the case of 89. We must have to do (89+89)= 178
So, only thats why it can continue the series like
178-89=89
Hope i can help you..
664-332=332
340-170=170
So in the case of 89. We must have to do (89+89)= 178
So, only thats why it can continue the series like
178-89=89
Hope i can help you..
Manikandan said:
1 decade ago
Take the 2nd, 4th and 6th numbers. Odd position=even position*2. For this sum it ll work as simple as that.
Satish said:
1 decade ago
Thanks saurabh ji.
Saurabh said:
1 decade ago
first divide by 2 and then add 8 it is clearly written
664/2=332
332+8=340
340/2=170
170+8=178
664/2=332
332+8=340
340/2=170
170+8=178
Chinna said:
1 decade ago
in the above split it into 3 parts each part contains 2 nos...
in the each part the 1st no is the double of the 2nd no...
that is
664=2*332
340=2*170
178=2*89
in the each part the 1st no is the double of the 2nd no...
that is
664=2*332
340=2*170
178=2*89
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