What is the next number in the sequence: 77,49,36,18…?

Hint: The given question is of sequence, here to solve such question first we need to know that how the numbers are adjusted for the given question, to find the property associated in the sequence we can use hit and trial method or if directly the associated property can be seen then we can find the next numbers of the given sequence.

Complete step-by-step answer:
The given question needs to find the next number for the given sequence, here we can see that the numbers are: 77,49,36,18…
Here we can see that the property associated in the sequence is:
First number: 77
Second number: product of the two numbers of the first number,
\[ \Rightarrow 7 \times 7 = 49\]
Third number: product of the two numbers of the second number,
\[ \Rightarrow 4 \times 9 = 36\]
Fourth number: product of the two numbers of the third number,
\[ \Rightarrow 3 \times 6 = 18\]
Fifth number: product of the two numbers of the fourth number,
\[ \Rightarrow 1 \times 8 = 8\]
Hence the answer for the sequence is eight.

Note: In order to solve the question associated with the sequence, we should observe the pattern which is related to the given question, also we have some standard sequence also known as arithmetic and geometric series whose formulas are also known to us.