Logical Reasoning - Number Series - Discussion
Discussion Forum : Number Series - Type 1 (Q.No. 16)
Directions to Solve
In each series, look for the degree and direction of change between the numbers. In other words, do the numbers increase or decrease, and by how much
16.
Look at this series: 80, 10, 70, 15, 60, ... What number should come next?
Answer: Option
Explanation:
This is an alternating addition and subtraction series. In the first pattern, 10 is subtracted from each number to arrive at the next. In the second, 5 is added to each number to arrive at the next.
Discussion:
84 comments Page 9 of 9.
Nandini said:
1 decade ago
Thanks for explaining the logic to find the answer. It's really helpful.
Shadab Akhtar said:
1 decade ago
First series;
80 - 70 = 10.
10 + 60 = 70.
70 - 55 = 15.
15 + 45 = 60.
60 - 40 = 20.
And, alternate series;
-70 + 60 = -10.
+60 - 55 = +5.
-55 + 45 = -10.
+45 - 40 = +5 and so on....
Hope this answer clarify all your doubt.
80 - 70 = 10.
10 + 60 = 70.
70 - 55 = 15.
15 + 45 = 60.
60 - 40 = 20.
And, alternate series;
-70 + 60 = -10.
+60 - 55 = +5.
-55 + 45 = -10.
+45 - 40 = +5 and so on....
Hope this answer clarify all your doubt.
DANISH said:
1 decade ago
But both options 50 and 20 are there so which one to choose?
Roshan Roy said:
1 decade ago
In this series they have divided numbers into two parts .This series goes like this 80, 10, 70, 15, 60, 20, 50, 25, 40, 30, 30, 35, 20 40, 10, 45 ...
80 70 60 50 -----> Decrement of 10.
10 15 20 25 -----> Increment of 5.
80 70 60 50 -----> Decrement of 10.
10 15 20 25 -----> Increment of 5.
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