更新1:
TO eelyw: COULD U PLZ STATE THE TERMS T, 1, 2, AND n COZ I DON'T KNOW WHT THE QUES. MEANT = =
Maths questions need help!!!
2009-06-24 2:08 am
SAM WON THE LOTTERY! HE SPENT 95p THE FIRST DAY, $1.90 THE NEXT, $2.85 THE NEXT, $3.80 THE NEXT AND SO ON. EACH DAY HE SPENT 95p MORE THAN THE DAY BEFORE UNTIL HE FINALLY SPENT THE LAST $190 OF HIS WINNINGS. HOW MUCH DID HE WIN IN TOTAL?
回答 (1)
2009-06-24 2:45 am
✔ 最佳答案
T(1) = 0.95T(2) = 0.95 + 0.95
T(n) = 190.
so 190 = 0.95 + (n -1)(0.95)
= 0.95n
so n = 190/0.95 = 200
Therefore, total win = 200[ 0.95 + 190]/2 = 100 ( 190.95) = 19095.
2009-06-23 18:48:48 補充：
For an arithmetic sequence T(n) = a + (n-1)d and Sum = n(first term + last term)/2.
收錄日期: 2021-04-25 22:36:55
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https://hk.answers.yahoo.com/question/index?qid=20090623000051KK01477