You can call it pemdas .( peranthasis,expression,multiply,divide,add,subtract
With tax, it would be 107.5% of 625.99. 107.5% is 1.075 in decimal form so you do 1.075(625.99). That gives the rounded answer of $672.94. :)
9 1/7 = 9.143
2 7/8 = 2.875
9.143 - 2.875 = 6.268
