It'spossibletodomanysimpletrickswithnumbers．Hereisonetrick，ifyoufollowtheinrtructions，youwillfindit'sreallyinteresting．First，writedownyourhousenumber．Forexample，ifyouraddressis73JinshangRoad，youwouldwri

　　It's possible to do many simple tricks with numbers．Here is one trick，if you follow the inrtructions，you will find it's really interesting．

　　First，write down your house number．For example，if your address is 73Jinshang Road，you would write down 73．After you write down your house address number，you double it．Then add 5to this doubled number．For example，if your address is 73and you double it，you will get 146．Then you add 5，you will get 151．

　　And then，multiply this number by 50．In our example here，you'll get 7550．The next step is to add your age to this total．For example，if you're 16years old，you should add 16to this total．In our example here，the result will be 7566．

　　After that，you have to add the number of days in a year，which is 365．In our example here，365added to 7566is 7931．

　　The final step is this：Subtract 615from the number that you have．Take away 615from the total．In our example，7931minus 615is 7316．

　　The result here-7316-is the trick．The first part of the number is the address and the last part of the number is the age of the person．That is，73is the address that we started with，and 16is the age that we used．

　　Isn't it interesting？Do you want to have a try now？

　　66．How many steps are there in the trick？___

　　A．Four

　　B．Seven

　　C．Nine

　　67．The third step is___．

　　A．+5

　　B．×50

　　C．-615

　　68．Tom is 38，he lives in 89Jinshang Road．If he plays this trick，he will get___ in the end．

　　A.3889

　　B.9150

　　C.8938

　　69．When you play this trick，___ is Not the number you have to use every time．

　　A.50

　　B.73

　　C.365

　　70．The best title of this passage is"___"．

　　A．A trick with numbers

　　B．An interesting problem

　　C．How to work out a trick．