how to solve missing number problems

Equation is made of a Numbers and variables. We can take a variable as missing number of an equation, for an example 2 * x = 10. Here 'x' is a variable and this is used to represent a missing number of this equation. We will discuss how to solve missing number problems.

Missing number can occur in sequence or in equation. We will discuss both cases.
Case 1 : Assume that we have a Set of numbers 1 ,3 , 5 , 7 , x , 13 , 17. Here in this set of numbers there is a missing number which is represented by variable 'x'. Now we have to find value of 'x'. We can see that in this set of numbers, all numbers are Prime Numbers. These prime numbers are in sequence. Prime number sequence consist of numbers 1, 3, 5, 7, 11, 13, 17.

Now we will match both Sets. From sets we will get to know the value of missing number 'x' that is equals to 11.

Case 2: As we know that equation is made of numbers and variables. Variable is used to show missing number. Assume that we have an equation 2x + 4 = 8. Here 'x' is the missing number. Now we will find value of 'x'.

We will separate variables and numbers on different sides of equation like:
2x = 8 – 4,
2x = 4,
x = 4 / 2,
x = 2.

Here missing value of equation is x = 2. We can verify value of missing number by placing it in equation.
2 * 2 + 4 = 8,
4 + 4 = 8,
8 = 8.

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