a small island has 2/5 of its surface covered by forest and 1/4 of the remainder of its surface by sand dunes.The island also has 90 hectares covered by farm land if the lsland is made up of only forest.what is the total area of the island.
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a small island has 2/5 of its surface covered by forest and 1/4 of the remainder of its surface by sand dunes.The island also has 90 hectares covered by farm land if the lsland is made up of only forest.what is the total area of the island.
a small island has 2/5 of its surface covered by forest and 1/4 of the remainder of its surface by sand dunes.The island also has 90 hectares covered by farm land if the lsland is made up of only forest.what is the total area of the island.
a small island has 2/5 of its surface covered by forest and 1/4 of the remainder of its surface by sand dunes.The island also has 90 hectares covered by farm land if the lsland is made up of only forest.what is the total area of the island.
题楼上已翻译题目的意思我就直接解了.
如果不要方程的话:
森林+沙丘:2/5+1/4=13/20
那么剩下的就是农场:单位“1”-13/20=7/20
90公顷=“7/20”:90÷7/20=1800/7公顷(好怪哦、、)=257又1/7公顷
答:the total area od the land is 257 1/7 hectares
2/5的森林
除了森林外有1/4的沙丘
还有90公顷的农场
求总面积
不知道1/4是除了森林之外的,还是小岛的,我估计是小岛的
s*(1-2/5)*(1-1/4)=90
s=200公顷
1800/7
一块小的岛屿有2/5被山林覆盖,剩下的1/4被沙丘覆盖。这个岛屿有90公顷用作于耕地,如果这个岛屿只由山林组成,那么这个岛屿的总面积是多少?
虽说翻译出来感觉不咋通,如果真叫我做的话我就设总面积为x,由题意可知:2/5x+(x-2/5x)X1/4+90=x。求得:x=200.希望对你有帮助。能不做方程么.感谢...由题意知:被山林和沙丘覆盖后剩余的占总面积的:1-2/5-(1-2/5)x1...
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一块小的岛屿有2/5被山林覆盖,剩下的1/4被沙丘覆盖。这个岛屿有90公顷用作于耕地,如果这个岛屿只由山林组成,那么这个岛屿的总面积是多少?
虽说翻译出来感觉不咋通,如果真叫我做的话我就设总面积为x,由题意可知:2/5x+(x-2/5x)X1/4+90=x。求得:x=200.希望对你有帮助。
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