It would be 42.82. In terms of decimals, then first digit- which would be the 8- is the tenths, the next-which would be the hundredths- and so on. If a number is five or higher, the number to the left would go up. If the number was 42.826, the rounded number would be 42.83. However, in this case, 4 is below five, which would make the number next to it stay the same.
