CHECK YOUR BRAIN There are a few ducks and goats in a field . Overall, 77 heads and 224 feet . What is the number of ducks ?

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Rajveer

CHECK YOUR BRAIN <pre class="tw-data-text vk_txt tw-ta tw-text-small" data-placeholder="Translation" id="tw-target-text" data-fulltext="" dir="ltr" style="unicode-bidi: isolate; font-family: inherit; border: none; padding: 0px 0.14em 0px 0px; position: relative; margin-bottom: 0px; resize: none; overflow: hidden; width: 237.5px; white-space: pre-wrap; color: rgb(33, 33, 33); height: 96px; font-size: 16px !important; line-height: 24px !important; background-color: rgb(255, 255, 255);">There are a few ducks and goats in a field . Overall, 77 heads and 224 feet . What is the number of ducks ?</pre>

27 апр. 2016 г., 9:10

Комментариев · 5

It depends on how many 3-legged goats and one-legged ducks there are.

28 апреля 2016 г.

duck = x

goat = y

x + y = 77-------> x = 77 - y

2x + 4y = 224 -----> simplified --------> x + 2y = 112

(77 - y) + 2y = 112

77 - y + 2y = 112

y = 112 - 77

y = 35

so, x = 77 - y

x = 77 - 35 = 42

42 ducks

27 апреля 2016 г.

42 ducks～

27 апреля 2016 г.

42 ducks

27 апреля 2016 г.

Let's all goats and ducks raise two feet. So 224-77*2 feet left, that's 70 feet. All goats fall down. Each ducks left 2 feet on ground. So there are half of 70 ducks, that's 35.

28 апреля 2016 г.