请教一道数学题,题目看不懂···
the table shows the number of each of the 5 stocks owned by mr.sami,if he was to sell 20 shares of stock x and buy 24 shares of stock y ,what would be the increase in the range of the numbers of shares of the 5stocks owned by mr sami?
答案选项如下:
请问这道题是什么意思?怎么做?