The masses of four objects were measured during a physics experiment. The first and the last each had a mass of 41.918 g. The second and the third objects each had a mass of 24.83 g. Find the total mass of the four objects. Write your answer in scientific notation.

For this case, the first thing we must do is add all the masses.
 We have then:
 M = (41,918) + (41,918) + (24.83) + (24.83)
 M = 133,496
 We now write the answer in scientific notation:
 M = 1.33496 * 10 ^ 2 grams
 Answer:
 The total mass of the four objects is:
 M = 1.33496 * 10 ^ 2 grams