When you're multiplying fractions by a whole number, flip the equation around. For the first one, ?/2x8=4 can be converted to 8/2=4. Or half of 8 is 4.
The next one is missing the whole number. It converts to 20/6 / 5/6, which is equal to 20/5 and 6/6, which is 4/1 or 4.
The last question can be converted to 18/3=?, which is 6. So the answer to that one is 1/6 x 18=3.
1. 1/2 x 8 = 4
2. 4 x 5/6 = 20/6
3. 1/6 x 18 = 3
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hope it helps
