Re: A gardener is planning a garden layout. There are two rectangular beds
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02 Jan 2019, 21:22
Hello marathonrunner,
Thanks for the post!
1. It says Bed A must contain 5 flowers or shrubs, and Bed A should have exactly 1 shrub and exactly 2 annuals, meaning that we have 2 places left. Since we only have 3 choices (annuals, perennials, shrubs), perennials will be our only choice (we cannot add annuals because it says we can only have 2, and we can't add shrubs because it says we can only have 1) 2. For Bed B, we are required to have 2 shrubs and AT LEAST 1 annual, again, 2 places left. But this time is different, because the number of annual can go from 1 up to 3 (we cannot add 4 annuals because the total will be more than 5), and the number of perennials change as we change the number of annuals. We need to discuss all 3 situations.
If we add 1 annual (meaning that we add 2 perennials): we choose 1 from 6 types of annual: 6, and we choose 2 from 4 types of perennials: 4*3 / 2=6 (choose 1 from 4, then choose 1 from 3 left, divided by 2 because we cannot use them repeatedly. That's how I calculated, you may have your own way), times them together we get 36. For the remaining 2 situations, we do the same thing. Hope my answer help!