Mr.wong has 100 mobile phones of the same model and they were worth $1580 each a month ago.The price of that model of mobile phone drops by 15% now. What is the total current value of those mobile phones owned by Mr wong?
更新1:
The expenditure of Sharon on traffic and clothing were $1500 and $800 respectively last month.If her expenditure on traffic reduce by 16% and that on clothing increases by 20% this month, what are sharon's repective expenditure on these two areas this month?