Read this word problem.In science class, Vicky did an experiment with an unknown solid. She started with 11 grams of the solid. During the experiment, the change in the mass of the solid was −4 grams. What was the final mass of the solid?To solve the problem, Jamal subtracted 11−(−4) and came up with an answer of 15 grams. Is Jamal correct? Why or why not?Choices:(A)Yes, Jamal is correct.(B)No. Jamal should have added 11+4 because he was trying to find the final, or total, mass.(C)No. Jamal should have added 11+(−4) because he needed to add the initial mass and the change in mass.
Q. Read this word problem.In science class, Vicky did an experiment with an unknown solid. She started with 11 grams of the solid. During the experiment, the change in the mass of the solid was −4 grams. What was the final mass of the solid?To solve the problem, Jamal subtracted 11−(−4) and came up with an answer of 15 grams. Is Jamal correct? Why or why not?Choices:(A)Yes, Jamal is correct.(B)No. Jamal should have added 11+4 because he was trying to find the final, or total, mass.(C)No. Jamal should have added 11+(−4) because he needed to add the initial mass and the change in mass.
Interpreting Change in Mass: Now, let's think about what the −4 grams represents. It's the change in mass, which means the solid lost 4 grams.So, we should actually subtract 4 grams from the initial mass to find the final mass.11−4=7 grams.
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