What is the last number in the number sequence given below? 10 : 10 : 20 : 45 : 110 : 300 : ? requires explanation, !

To get from the first number to the second number the equation is 10x0.5+5=10
Thereafter the equation to get to the next number is 10x1.0+10=20
Thereafter the equation to get the next number is 20x1.5+15=45
Thereafter the equation to get the next number is 45x2.0+20=110
You can notice the pattern, the first number is what the last number was, you increase the second number by 0.5 and you increase the third number by 5.
Following this pattern to find the last number you do 110x2.5+25. This equation results in the number 300. Now time for the last number. You input 300x3.0+30. The answer results in 930. Therefore, the missing number is 930. 

Hello,

10 times 0.5 plus 5 equals 10
10 times 1 plus 10 equals 20 
20 times 1.5 plus 15 equals 45
45 times 2 plus 20 equals 110
110 times 2.5 plus 25 equal 300
300 times 3 plus 30 equals 930

Hope this helps

The answer to this question is c