数学题:财务室会计结账时，发现账面上少了890.1元钱。经核对是把小数点点错一位。原数是多少？

数学题解答：1、算术方法：

账面上钱少了，说明是把小数点向左移了一位。

小数点向左移动一位，得到的数缩小为原数的1/10。

那么少的890.1元钱，就是原数的1 – 1/10 = 9/10。

所以原数是：890.1 ÷ (1 – 1/10) = 989（元）

2、如果用方程做，还可以设现在的钱数为x元。

解：设现在的钱数为X元

10X-X=890.1

x=98.9

98.9×10=989（元）

推荐阅读：
Recursive Depth First Search Algorithm to Delete Leaves With a G　 Algorithms to Determine a Palindrome Number　 Algorithm to Compute the Fraction to Recurring Decimal of the Tw　 Algorithms to Check if Array Contains Duplicate Elements　 Recursive Depth First Search Algorithm to Compute the Sum of Nod　 How to Convert Integer to the Sum of Two No-Zero Integers?　 Algorithm to Generate the Spiral Matrix in Clock-wise Order　 How to Remove the Duplicates from Sorted List (Leaving Only Dist　 How to Sort a Linked List by Converting to Array/Vector?　 Know The Effective and Smart SEO Reporting Tool You Must Use