1. The sum of a number and 13 equals 3 times the result of the number minus 11. Find the number.
2. Find 2 consecutive even numbers such that 3 times the larger number exceeds 2 times the smaller number by 22.
3. There were x passengers in a train leaving from the terminal. At the first stop, 1/4 of the passengers got off, and 28 passengers got on the train. Find, in terms of x, the number of passengers in the train when it left the first stop.
數學題目!!!!
2007-05-18 7:34 am
回答 (2)
2007-05-18 7:53 am
✔ 最佳答案
1.let x be the number
x + 13 = 3(x - 11)
x + 13 = 3x - 33
2x = 46
x = 23
2.
let x be the larger number
then the smaller one will be x - 2
3x - 2(x - 2) = 22
3x - 2x + 4 = 22
x = 18
3.
let y be the number of passengers in the train when it left the first stop
y = (3x/4) + 28
2007-05-25 12:16 pm
1)Let the number be n
n+13=3(n-11)
n+13=3n-33
46=2n
n=23
2)Let the smaller number be x and the larger number be x+2
3(x+2)=22+2x
3x+6=22+2x
x=16
∴the smaller number is 16 and the larger number is 18
3)the number of passengers in the train when it left the first stop
=(1-1/4)x+28
=(3/4)x+28
n+13=3(n-11)
n+13=3n-33
46=2n
n=23
2)Let the smaller number be x and the larger number be x+2
3(x+2)=22+2x
3x+6=22+2x
x=16
∴the smaller number is 16 and the larger number is 18
3)the number of passengers in the train when it left the first stop
=(1-1/4)x+28
=(3/4)x+28
收錄日期: 2021-04-23 23:39:37
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