Question

Tom 的年龄为 $T$ 岁，也等于他三个孩子年龄之和。 $N$ 年前他的年龄是当时三个孩子年龄之和的两倍。求 $T/N$ ？

Tom's age is $T$ years, which is also the sum of the ages of his three children. His age $N$ years ago was twice the sum of their ages then. What is $T/N?$

$2$

$3$

$4$

$5$

$6$

答案：D

知识点：年龄问题一次方程

难度评级：1290

解答：

$N$ 年前 Tom 年龄为 $T-N$ 。三个孩子每人少 $N$ 岁，所以他们当时总年龄为 $T-3N$ 。

条件给出因而 $5N=T$ ，所以 $T/N=5$ 。 $T-N=2(T-3N),$

所以正确答案是 D。

Tom's age $N$ years ago was $T-N.$ His three children were each $N$ years younger, so their ages then totaled $T-3N.$

The condition gives $T-N=2(T-3N),$ so $5N=T$ and $T/N=5.$

Thus, the correct answer is D.

2007 AMC 12B 第 8 题

答案：D

难度评级：1290

解答：

其他年份的第 8 题