Number series
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Number series
Hello,
My dd came across one of the number series
11 14 22 16 __ __
It is standard format paper so there is no possibility of looking in multiple options.
she thinks it is two series running together with the answers being 44 and 18
11 22 44.........double the previous number
14 16 18.........+4 to previous number
But the answer is 33 and 18
my trouble is there no reason for the answer not to be 44 with her explanation.....
she says to prove it to bee 33 they should give series a bit longer to be obvious that it is 11 times table....
Do these unclear questions appear in actual test and if they do both the answers are considered correct?
Please help....
My dd came across one of the number series
11 14 22 16 __ __
It is standard format paper so there is no possibility of looking in multiple options.
she thinks it is two series running together with the answers being 44 and 18
11 22 44.........double the previous number
14 16 18.........+4 to previous number
But the answer is 33 and 18
my trouble is there no reason for the answer not to be 44 with her explanation.....
she says to prove it to bee 33 they should give series a bit longer to be obvious that it is 11 times table....
Do these unclear questions appear in actual test and if they do both the answers are considered correct?
Please help....
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- Location: Buckinghamshire
Re: Number series
It is an ambiguous question. The real tests (depending upon the school/area) are usually very carefully proof-read to iron out any ambiguities like this. I can only recall one occasion when an error was identified on a real paper - a few years ago in Herts.
Re: Number series
hello all
How do you know which sequence to use on these sort of questions.?
22, 21, 23, 23, 24, 25, 25 (....)
The way I look into this is that you can go both ways...22 to 23, 23 to 24, 24 to 25
Alternatively, use 21 instead but then it jumps by 2..21 to 23, 23 to 25 and so on
Answer is 27 but why ??
Also I have one more:-
93, 92, 95, 95, 97, 98 (...)
Answer is 99 but why?
Many Thanks !
How do you know which sequence to use on these sort of questions.?
22, 21, 23, 23, 24, 25, 25 (....)
The way I look into this is that you can go both ways...22 to 23, 23 to 24, 24 to 25
Alternatively, use 21 instead but then it jumps by 2..21 to 23, 23 to 25 and so on
Answer is 27 but why ??
Also I have one more:-
93, 92, 95, 95, 97, 98 (...)
Answer is 99 but why?
Many Thanks !
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Re: Number series
22 21 23 23 24 25 25
every other number ncreasing by one
22 23 24 25
every other number increasing by two
21 23 25 27
every other number ncreasing by one
22 23 24 25
every other number increasing by two
21 23 25 27
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Re: Number series
93 92 95 95 97 98
93 95 97 ... 99
every other number increasing by two
92 95 98
every other number increasing by three
93 95 97 ... 99
every other number increasing by two
92 95 98
every other number increasing by three
Re: Number series
So surely answer could be 99 or 101...how do you know which one to use or am i having a blond moment here ?faitaccompli wrote:93 92 95 95 97 98
93 95 97 ... 99
every other number increasing by two
92 95 98
every other number increasing by three
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Re: Number series
Because it is in sequence - so it needs to match the penultimate number in the list.
ie.
93 92 95 95 97 98 99
ie.
93 92 95 95 97 98 99
Re: Number series
ok, but then both sequences would give you 101 not 99 and the answer is 99 on the answers ??faitaccompli wrote:Because it is in sequence - so it needs to match the penultimate number in the list.
ie.
93 92 95 95 97 98 99
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Re: Number series
Manny0311 wrote:ok, but then both sequences would give you 101 not 99 and the answer is 99 on the answers ??faitaccompli wrote:Because it is in sequence - so it needs to match the penultimate number in the list.
ie.
93 92 95 95 97 98 99
The number in bold and underscored is the missing number! so the original sequence was
93, 92, 95, 95, 97, 98, ?
Re: Number series
Going backwards from the question mark every other number goes down by 2, i.e. 97, 95, 93, ... So the preceding number (the question mark) was 99.
The number after 99 would be 101 because every other number preceding it goes up by 3, i.e. 92, 95, 98, ... However, you are not required to give this number.
The number after 99 would be 101 because every other number preceding it goes up by 3, i.e. 92, 95, 98, ... However, you are not required to give this number.