1.
72 marbles are divided into two groups. 7 times the number of marbles in the smaller group is equal to 5 times that in the larger group. Find the number of marbles in the smaller group.
Let the number of marbles in the smaller be x, then that in the larger group is (72-x)
2.
The total age of Hebrew and his son is 51. 3 years ago, Hebrew is 8 times as old as his son. Find the current age of Hebrew’s son.
[在線等~] F.1數學題兩條
2008-12-05 6:25 am
回答 (2)
2008-12-05 6:46 am
✔ 最佳答案
1.7x = 5 * (72 - x)
7x = 360 - 5x
12x = 360
x = 30
2
Let Hebrew's age be x and his son is y
x + y = 51
(x - 3) = 8 * (y-3)
(51 - y - 3) = 8 y - 24
51 - 3 + 24 = 8y + y
72 = 9y
y = 8
Hebrew's son is 8 years old
2008-12-05 6:49 am
1. Let x be the number of marbles in the smaller group,
7x=5(72-x)
7x=360-5x
7x+5x=360
12x=360
x=30
2. Let x be the current age of Hebrew's son.
x+3+8x+3=51
9x=51-6
x=45/9
x=5
7x=5(72-x)
7x=360-5x
7x+5x=360
12x=360
x=30
2. Let x be the current age of Hebrew's son.
x+3+8x+3=51
9x=51-6
x=45/9
x=5
收錄日期: 2021-04-13 16:17:35
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081204000051KK01878