一亿张试卷用英语可以说成 "one hundred milpon test papers"。这个数量的来源可能是某种统计，比如一个学校或考试机构在一定时间内发出了一亿张试卷。

例句：

The school administration announced that they had printed one hundred milpon test papers for the upcoming exams.
The testing agency reported that they had distributed one hundred milpon test papers to schools across the country.

中文翻译：

学校管理层宣布，他们已经为即将到来的考试印刷了一亿张试卷。
考试机构报告说，他们已经向全国各地的学校发放了一亿张试卷。