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Ulleksa [173]
2 years ago
8

Jeff's mother gave him money. he used an equal amount of money each day. at the end of the 7th day, he was left with 1/4 of how

much he had at first. at the end of the 9th day, he was left with $10. how much did jeff receive from his mother?
Mathematics
1 answer:
skelet666 [1.2K]2 years ago
4 0

Jeff received 280$ from his mother

Such questions are the simplest as it needs you to just write the conditions accordingly which then simplifies and provides you the answer.

This question can be solved using two tricks which are shown below:-

Trick  1 :

1 – 1/4 = 3/4 (used for the 1st 7 days)

1/4 – 410 (used for 8th and 9th days)

(3/4)/7 ——- (1/4 – 10)/2

(3/4) x (2/7) = 3/14 ——- (1/4 – 10)

1/4 – 3/14 = (7 – 6)/28 = 1/28 ——- 10

28/28 ——- 10 x 28 =$ 280

Trick 2 :

7 days ——- 3/4

1 day ——- 3/28

2 days ——- 6/28

6/28 ——- (1/4 – 10) = 7/28 – 410

1/28 ——- 10

28/28 ——- 10 x 28 = $280

Thus Jeff received 280$ from his mother.

Learn more about simple math here :

brainly.com/question/23678

#SPJ4

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