Final answer:
Multiplying both sides by 1000 to clear the decimals is preferred over dividing both sides by 0.02 because it eliminates the decimals and simplifies the equation.
Step-by-step explanation:
In this case, the student wants to solve the equation 0.02x - 0.004 = 0.028. Your classmate's method of dividing both sides by 0.02 is not advantageous because it doesn't eliminate the decimals. Dividing by 0.02 would give you x - 0.2 = 1.4. This method would require additional steps to solve, whereas multiplying both sides by 1000 to clear the decimals right away would give you 20x - 4 = 28.
By multiplying both sides by 1000, we get 20x - 4 = 28. From here, we can proceed to solve the equation by adding 4 to both sides to isolate the variable, resulting in 20x = 32. Finally, dividing both sides by 20, we find that x = 1.6.