After the first term in a sequence of positive integers, the ratio of each term to the term immediately preceding it is 2 to 1. What is the ratio of the eighth term in this sequence to the fifth term?
Can someone please explain? :)
Can someone please explain? :)
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its of this type -
1,2,4,8,16,32,64,128,256 etc..
As you can see, ration of any term to its preceding number is 2:1
let fifth be x
so sixth = 2x
and seventh = 4x
and eighth = 8x
so eight to fifth = 8x/x = 8:1
Looking at the answer more closely,
you'll realize its 2^3 : 1
or 2^(8-5) : 1
or 2 raised to term no1 - term no2 : 1
;) So now you know how to do these type of questions :)
1,2,4,8,16,32,64,128,256 etc..
As you can see, ration of any term to its preceding number is 2:1
let fifth be x
so sixth = 2x
and seventh = 4x
and eighth = 8x
so eight to fifth = 8x/x = 8:1
Looking at the answer more closely,
you'll realize its 2^3 : 1
or 2^(8-5) : 1
or 2 raised to term no1 - term no2 : 1
;) So now you know how to do these type of questions :)
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If the first term is a, then the second term is 2a, third is (2^2)a, 4th is (2^3)a
5th is (2^4)a and 8th is (2^7)a and ratio is 2^7/2^4=8 to 1
5th is (2^4)a and 8th is (2^7)a and ratio is 2^7/2^4=8 to 1
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1 a
2 2a
3 2*2a
.
.
.
2^(n-1)a
2^(8-1)a
---------- =
2^(5-1)a
2^3
2 2a
3 2*2a
.
.
.
2^(n-1)a
2^(8-1)a
---------- =
2^(5-1)a
2^3