Lightning Calculator

[Lightning Calculator]
Testing the ability of oral and mental arithmetic to improve logical thinking judgment and response ability.
[Main Functions]
1.The system gives questions randomly and adds, subtracts, multiplies and divides any number.
2.Time limit and rapid response;
3.Wrong answer means the end of the answer.
[Opinion & Feedback]
If you have any problems, please contact me in time!
Mailbox: WoodrowEugeneuMjFa@yahoo.com.