1)The sum of three consecutive numbers minus 4 times the smallest number equals 1.Find the three number.
2)Andy is now 12 years old.5 years later,Andy will be1/3 as old as his mother.Find the age of his mother now.
maths,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
2006-10-17 12:17 am
回答 (8)
2006-10-17 12:22 am
✔ 最佳答案
1)The sum of three consecutive numbers minus 4 times the smallest number equals 1.Find the three number.Let the smallest number be x, then(x+1),(x+2),
x+(x+1)+(x+2)-4x=1
-x+3=1
-x=-2
x=2
so the smallest number is 2
the(2+1)=3
then(2+2)=4
2)Andy is now 12 years old.5 years later,Andy will be1/3 as old as his mother.Find the age of his mother now.
let x be the age of his mother
(12+5)=(1/3)x
17=x/3
x=51
so the age of his mother is 51-5=46
2006-10-17 3:33 am
2. 46
2006-10-17 1:47 am
1)2
2)51
2)51
2006-10-17 1:28 am
(1) They are 1, 2, 3
Let X = the smallest numbr
X + (1+X) +(2+X) -(4X) = 1
X = 2
(2) Andy's mother is now 46.
Let Andy' mother age is y now.
(12 + 5) = 1/3 X ( y + 5)
17 = 1/ 3 y + 5/3
17 - 5/3 = 1/3 y
3(17-5/3) = y
51 - 5 = y
y = 46
Let X = the smallest numbr
X + (1+X) +(2+X) -(4X) = 1
X = 2
(2) Andy's mother is now 46.
Let Andy' mother age is y now.
(12 + 5) = 1/3 X ( y + 5)
17 = 1/ 3 y + 5/3
17 - 5/3 = 1/3 y
3(17-5/3) = y
51 - 5 = y
y = 46
2006-10-17 12:27 am
1. x+(x+1)+(x+2)-4x = 1
x = 2
2. 12+5=x/3
x = 51
x = 2
2. 12+5=x/3
x = 51
2006-10-17 12:25 am
1. 2,3,4
2. 46
2. 46
2006-10-17 12:23 am
let x be the smallest number
x+(x+1)+(x+2)-4x=1
3-x=1
x=2
let x be the age of Andy's mother age
(x+5)/3=12+5
x+5=51
x=46
2006-10-16 16:24:25 補充：
1) the three numbers are 2,3,4
x+(x+1)+(x+2)-4x=1
3-x=1
x=2
let x be the age of Andy's mother age
(x+5)/3=12+5
x+5=51
x=46
2006-10-16 16:24:25 補充：
1) the three numbers are 2,3,4
收錄日期: 2021-04-12 20:23:07
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20061016000051KK01621