简便运算:0.9+0.98+0.997+0.9996+0.99995

问题描述:

简便运算:0.9+0.98+0.997+0.9996+0.99995

原式=1+1+1+1+1-0.1-0.02-0.003-0.0004-0.00005=4.87655

0.9+0.98+0.997+0.9996+0.99995
=1-0.1+1-0.02+1-0.003+1-0.0004+1-0.00005
=5-0.12345
=4.87655