(1)if 500 isthe multiple of 100 that is closest to x and 400 is the multiple of 100 that is closest to y, which multiple of 100 is closest to x+y?(选E) 1)x <500 2)y<400 请问这道题的思路是怎样 (2) 没有读懂的一句话 2n is divisible by twice as many positive integer as n (3)Tanya prepared 4 different letters to be sent to 4 different addresses. for each letter , she prepared an envelope with its correct address. if the 4 letters are to be put into the 4 envelopes at random, what is the probability that only 1 letter will be put into the envelope with its correct address?(I/3) (4) Ann 450000 Bob 360000 Cal 190000 Dot 210000 Ed 680000 the table shows the total sales recorded in July for the 5 salespeople at Acme truck sale, it was discovered that one of Cal's sale was incorrectlt recorded as one of Ann's sales. after this error was corrected, Ann's total sales were still higher than Cal's total sale, and the median of the 5 sales total was 330000, what was the value of the incorrectly recorded sale?(120000) 偶是这样想的, 没有变以前, 他们5 个的sale 从小到大排列是: Cal, Dot, Bob, Ann, and Ed, 所以Bob的sale 是media, 为360000, 变化后中位数变成了330000, 其他人的收入都没有变, 所以 Cal 的sale 就变成了330000了啊, 是不是这样啊? | 
