Add 5 to 3 times of a number and the sum is 20. What is no.
回答 (3)
2008-10-12 4:04 pm
✔ 最佳答案
由於先乘除後加減, 所以將文字轉番做number equation先搞掂乘除先。let the number be x.
"3 times of a number" means x times 3, i.e. 3x
"add 5 to", i.e. +5
"the sum is 20", i.e. =20
∴5+3x=20
3x=20-5
3x=15
x=15/3
x=5
參考: 自己計^^
2008-10-12 6:43 am
Let d b the number.
3d+5=20
3d =20-5
3d =15
d =15/3
d =5
Therefore, the number is 5.
3d+5=20
3d =20-5
3d =15
d =15/3
d =5
Therefore, the number is 5.
參考: my maths knowledge
2008-10-12 6:18 am
Let y be the number.
5+3y=20
3y=15
y=5
5+3y=20
3y=15
y=5
收錄日期: 2021-04-19 20:32:14
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