The difference in understanding is because the initial author calculated in terms of number of servings while you calculated directly based on the number of cups of Pasta
What you did gives you the answer on the combined step itself and you don't need the last step "From A we know that he will Prepare 8 servings. Hence he would need 8/(4/1.5) = 3 Cups."
However, if you calculated based on the number of servings, it would have worked out as shown below
1.5 cups of pasta needed for making 4 servings.
based on statement 2, 6 cups of Pasts will give us 6*4/1.5=16 servings. --a
These 16 servings were made last time. We know from statement 1
Number of servings next time= half the number of servings of pasta that he made last time.
Hence, next time servings=8
how many cups of pasta would be required to make 8 servings of pasta?
4 servings=1.5 cups of pasta
8 servings=3 cups of pasta (8/(4/1.5) = 3 Cups.)
Hope this helps!
Next time = 1/2 last time - we don't have any other info
Last time = 6
6/2 = 3?
From A we know that he will Prepare 8 servings. Hence he would need 8/(4/1.5) = 3 Cups.
I didn't understand the above step...
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