Hi there!
The question is asking us to find the common difference (or ratio) of the sequence.
First of all, what is the difference between a common difference and a common ratio?
Common Difference
This is the amount we add/subtract to get to the next term. This only happens in an arithmetic progression.
A common ratio, on the other hand, is an amount that we multiply/divide by to get to the next term. This happens in geometric progressions.
With this in mind, we will take a look at the sequence provided here:
3, 7, 11, 15...
Which operation do we perform to obtain the next term? Is it addition, subtraction, multiplication, or division? Well, clearly, we add 4 each time. So we automatically know that in this case, we have the common difference. That difference is 4.
Have a fantastic day!
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