Fifty thousand more than 15,343,014 is 15,393,014.

25,981 is 3 less than 25,984

The key to figuring out this kind of problem is to understand the decimal numeration system. Moving from right to left, each place is worth 10 times more than the place before it. Moving from left to right, each place is worth 10 times less.

Also, the numbers form a pattern. The first three -- moving from right to left, are units (ones), tens and hundreds. The next three are **the same thing**, but in the thousands family. The next three are **the same thing**, but in the millions family.

So, in 1X2,345,789, the X is in the second place in the third family, so it is tens of millions.

In 23X,456, the X is in the first place in the second family, so it is units (ones) of thousands.