六年级奥数，请大家帮忙加50分。

3.6-3.6*(1/4)+5(7/8)*5/[(7/8)*5]=3.6*(3/4)+1=2.7+1=3.7

[(0.34 x 2400 x 0.25+3x(31/4)+26.25/(1/3)]/(2/13)=(204+93/4+78.75)* 13/2 = 3.6 * 13/2 = 1989

9.81x 10%+(1/2)x 98.1+0.049 x 981 = 9.81x(0.1+5+4.9)= 9.81x 10 = 98.1

126和49点1除以25 =(126 x49+1)x4/100 =[(126 x50)-126+1。