中一數學題－ohe09nz81r的部落格

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中一數學題

發問:

1.Find two fractions with different denominators(分母)such that their sum is 19/24.2.A shopkeeper raised the price of a table by 20%. Later he sold the table ai a discount of 20%. How did the selling price compare with the original price? Use an example to explain.3.In a class of 40 students, 45% of them are boys... 顯示更多 1.Find two fractions with different denominators(分母)such that their sum is 19/24. 2.A shopkeeper raised the price of a table by 20%. Later he sold the table ai a discount of 20%. How did the selling price compare with the original price? Use an example to explain. 3.In a class of 40 students, 45% of them are boys and 55% of them are girls. What are the number of boys and girls respectively?

最佳解答:

1.Find two fractions with different denominators(分母)such that their sum is 19/24. Ans : 19/24=16/24 + 3/24= 2/3+1/8// 2.A shopkeeper raised the price of a table by 20%. Later he sold the table ai a discount of 20%. How did the selling price compare with the original price? Use an example to explain. let the cost of table is $ x A shopkeeper raised the price of a table by 20%-->Profit = 0.2x Later he sold the table ai a discount of 20%-->the sell price = 0.8x so 0.8x - x=0.2x -0.2x=0.2x -1=1 that mean the cost of table is equal to any number .....like 1000, 2000 3.In a class of 40 students, 45% of them are boys and 55% of them are girls. What are the number of boys and girls respectively? Ans: boys=40x45%=40x45/100=18// girls= 40-18=22//