Select the option that is related to the third number in the same way as the second number is related to the first number.
20 : 440 :: 15 : ?
- A157
- B222
- C255
- D250
Solution & Step-by-step Explanation
Let's find the relationship between 20 and 440:
20
2
+20=400+20=420
=440
Let's try another variant:
20×(20+2)=20×22=440
Alternatively:
20
2
+2×20=400+40=440
Applying this mathematical relation n×(n+2) to 15:
15×(15+2)=15×17=255
Therefore, the missing number is 255.
20
2
+20=400+20=420
=440
Let's try another variant:
20×(20+2)=20×22=440
Alternatively:
20
2
+2×20=400+40=440
Applying this mathematical relation n×(n+2) to 15:
15×(15+2)=15×17=255
Therefore, the missing number is 255.