NO.PZ2021061603000013
问题如下：
The following is a frequency polygon of monthly exchange rate changes in the US dollar/Japanese yen spot exchange rate for a four-year period. A positive change represents yen appreciation (the yen buys more dollars), and a negative change represents yen depreciation (the yen buys fewer dollars).
Based on the chart, yen appreciation:
选项：
A.occurred more than 50% of the time B.was less frequent than yen depreciation C.in the 0.0 to 2.0 interval occurred 20% of the time解释：
A is correct. Twenty observations lie in the interval "0.0 to 2.0"and six observations lie in the "2.0 to 4.0"interval. Together, they represent 26/48, or 54.17%, of all observations, which is more than 50%.
这一道题哪里有说观察对象是48个呢，怎么得出的48？
