On a graph with y values ranging from 112020 to 982192 what is a reasonable scale to use on a y-axis with 10 tick marks

The best way to do this is to subtract the lowest number from the greatest number and divide it by the number of tick marks before rounding off. So,

981,192 - 112,020 = 869,172

869,172/10 = 86,917.20

The value can be rounded off to 100,000. The scale of each tick mark will be 100,000.