Question

Find the missing numbers.
12 14 16 18 20 ? ?
A) 21, 22
B) 22, 23
C) 22, 24
D) All the above
E) None of these

Answer 1

Hint: To solve this question, we have to find the difference between the two numbers i.e. previous and next numbers. Moving from left to right two numbers is increasing every time or can say moving from right to left two numbers should decrease every time.





Complete step by step solution:According to the question, if we see the first number which is '12', and the next number which is '14' there is a difference of '2' which can be found by subtracting the two numbers like \[14\text{ }-\text{ }12\text{ }=\text{ }2\]

Similarly, the next two numbers are '14' and '16' which when subtracted like 16 - 14 = 2, gives a difference of '2'. Hence '16' and '18', '18' and '20' also have a difference of '2' in the same way.
Therefore, let's assume that number next to the '20' is 'x'. As from above, we know that the difference between 'x' and '20' will be '2', therefore\[x\text{ }-\text{ }20\text{ }=\text{ }2\].
To find x, '20' will go to the right-hand side and will be added with '2' as it was subtracted in the left-hand side, \[x\text{ }=\text{ }2\text{ }+\text{ }20\text{ }=\text{ }22\]. Hence, the number after the '20' will be '22'. Similarly, in this way, the number after '22' will be '24' as there is also a difference of '2' between them.



Option ‘C’ is correct



Note: The above question can always be solved by finding the difference between two numbers that are already given and after finding the difference the missing number can be found. As we know there is a difference of '2' between every two numbers, the next can also be found by adding '2' in the previous one, like 12 + 2 = 14 and 16 + 2 = 18. Now for finding the next number after '20', add '2' to it such as \[20\text{ }+\text{ }2\text{ }=\text{ }22\]and similarly,\[22\text{ }+\text{ }2\text{ }=\text{ }24\].