Can anyone solve this math puzzle?

[Alex H]

The first day Jenny went fishing, she caught exactly 31416 pounds of fish!Even though she had more fish than she knew what to do with, she decided to go fishing again the next day. And she caught exactly 40% of what she caught the day before. Which was still a lot of fish. She continued fishing every day. And every day she caught exactly 40% of what she caught the previous day. If she continued fishing every day for twenty years, how many pounds of fish, total, would she catch? Please round to the nearest pound.

[Ashwin]

u hav to use geometric progression.ans is314126+314126*.4+314126*.4*.4. . ... .. . . . 314126{ 1(1-(0.4)^20*365-1)/1-0.4)}

[Christina]

The answer is 64,4340.

[yousedummy]

This must be a popular homework assignment for teachers, given its frequent appearance in Yahoo Answers.

[C_F15H]

Use a geometric sequence. Because it is a convergent series because r < 1, it should lead up to a number.r= .4t1=31416Using these numbers and this equation:t1 / 1-rwe can find how many pounds she caught!31416 / (1-.4)You get 52360 pounds of fish!!

[Bramblyspam]

If Jenny continued fishing forever, the total would be 31416 * (1/0.4) pounds. That's 31416 * 2.5, or 78540 pounds.After 20 years, she will have fished 20*365.25 = 7305 days. At that point, her daily catch is 31416 * (0.4)^7305, which for all practical purposes is zero. Basically, all the fish she catches from that point forward wouldn't amount to anything.Hence, the total catch for 20 years would be 78540 pounds.

[tom_2727]

52360 pounds of fish. She actually has caught this much fish (rounded up) by day 13. The rest of the 20 years, she caught less than 0.5 pounds total.

[SWAPNIL]

in 20 years there are 4 leap yearsso the total number of days become(16*365)+(4*366)=7304the first day she caught 31416 poundsthe second day 31416 *40/100 ; 40% of totalthe third day 31416 *40/100 *40/100 ;40% of the second dayand so onthis will give31416 +31416 *40/100+31416 *(40/100)^2+31416 *(40/100)3+....... +31416 (40/100)^(7304-1)this is a Geometrical progression31416 (1+40/100+(40/100)^2+(40/100)^3+...+(40/100)^7303now sum of n terms of GP = {a(1-r^n)}/(1-r)a=1r=40/100n=7303placing the corresponding values we get = 1{1-(2/5)^7303}/1-(2/5) =1/(3/5)=5/3total pounds of fish caught in 20 years =31416 * 5/3=52360that should be your answer or very close to it, whatever.