My answers always seem to be off by about 10 cents and I know it has to do with my rounding. I normally try not to round off my figures until I reach the end of the equation but I thought that when dealing with dollars and cents, you're supposed to round things off or try to keep all figures with the same amount of decimal places. Whatever way it is, I'd like to know exactly how I'm supposed to know how many decimal places to keep.

Here's the question I'm working on:

Mr. Parker structured his will so that each of his four children will receive half as much from the proceeds of his estate as his wife, and each of 13 grandchildren will receive 1/3 as much as each child. After his death, $759,000 remains after expenses and taxes for distribution among his heirs. How much will each child and grandchild receive?

My work:

Total $ left to wife = x

Total $ left to each child = 0.5x

Total $ left to each grandchild = (1/3)(0.5x)

Total $ in will = Total $ left to wife + Total $ left to children + Total $ left to grandchildren.

1) $759,000 = x + 4(0.5x) + 13((1/3)(0.5x))

2) $759,000 = x +2x + 2.1667x

3) x = $759,000/5.1667 = $146,902.2781 left to wife

therefore $ left to each child = 0.5($146,902.2781) = $73,451.1391

(correct answer for $ left to each child is supposed to be $73.451.62. I purposely didn't round off in my work here. When I round the 1/100th decimal place in all places or various places, I still don't get exactly the right cents amount.

Can any of you guys tell me a reliable method of rounding when it comes to this stuff? I've never been able to master it.