Problem 1
We multiply the fractions 1/2 and 1/3 to get (1/2)*(1/3) = 1/6
Use the rule that (A/B)*(C/D) = (A*C)/(B*D)
We can think of the problem like this: Consider there are 12 slices total. Half of which is 6 since 6/12 = 1/2. Then we take 1/3 of that 6 to get (1/3)*6 = 2. So if there are 12 slices to start, Linda gets 6 slices (ie half of the pizza). She then gives 2 slices to her seatmate (one third of what Linda got). The seatmate gets 2/12 = 1/6 of the pizza.
Answer: 1/6
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Problem 2
Like before, we multiply the fractions given to us.
(4/5)*(1/3) = (4*1)/(5*3) = 4/15
Answer: 4/15 kg
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Problem 3
Same idea as the previous two problems.
(6/8)*(1/3) = (6*1)/(8*3) = 6/24 = 1/4
Answer: 1/4 kg