Which is the missing number: 9876, 6447, 2527, x?

This question presents an interesting pattern.

The rule/pattern to be followed here is:

Left side of the number looking at the previous one: (First digit x Third digit + 1)

Right side: (Second digit x Fourth digit -1)

For example, let us take 6447. Let us look at it's previous number, 9876.

Now, and

that is how we got 6447

Again, for the third number, 2527, let us look at it's previous number, 6447

Now,

and

that is how we got 2527

Going by the same logic, the missing number should be 534.

This we got by applying the rule of the pattern as:

and

Thus, we got 534.

in geometry, parallel lines are lines in a plane which do not meet; that is, two lines in a plane that do not intersect or touch each other at any point are said to be parallel. by extension, a line and a plane, or two planes, in three-dimensional euclidean space that do not share a point are said to be parallel.