Math Riddle

Bourn · Jul 8, 2017

If you set aside a penny on the 1st day, 2 pennies on the 2nd day, 4 pennies on the 3rd day, and kept doubling everyday for a month. How much money would you have at the end of the month.

slapshot · Jul 8, 2017

HarryCaray · Jul 8, 2017

Depends on how many days there are in the month.

In a 30 day month you would have over 10 million.

Bourn · Jul 8, 2017

slapshot said:
$714

LOL not even close.

Bourn · Jul 8, 2017

HarryCaray said:
Depends on how many days there are in the month.

In a 30 day month you would have over 10 million.

Boom!! Great job

HarryCaray · Jul 8, 2017

I'm going to bet 1 penny on a +100 wager and keep rolling it forward. See if I can hit 30 in a row.

fightgood · Jul 8, 2017

This riddle is sometimes asked like this: Would you rather have a million dollars or a penny that is doubled every day for a month? Most people say a million dollars.

slapshot · Jul 8, 2017

7 days $1.28
14 days $163.84
21 days 20,971.52
28 days 2,684,354.56

I could be wrong but close enough

OfftheSheet · Jul 8, 2017

10,737,417

based on 30 days

PatsFan1283 · Jul 8, 2017

That's not a riddle, it's multiplication.

slapshot · Jul 8, 2017

slapshot said:
$714

Bourn said:
LOL not even close.

OfftheSheet said:
10,737,417

based on 30 days

714 / 417 just had the numbers backwards

OfftheSheet · Jul 8, 2017

1

2[SUP]16[/SUP]

=

65,536

2[SUP]32[/SUP]

=

4,294,967,296

2[SUP]48[/SUP]

=

281,474,976,710,656

2[SUP]64[/SUP]

=

18,446,744,073,709,551,616

2[SUP]80[/SUP]

=

1,208,925,819,614,629,174,706,176

2[SUP]1[/SUP]

=

2

2[SUP]17[/SUP]

=

131,072

2[SUP]33[/SUP]

=

8,589,934,592

2[SUP]49[/SUP]

=

562,949,953,421,312

2[SUP]65[/SUP]

=

36,893,488,147,419,103,232

2[SUP]81[/SUP]

=

2,417,851,639,229,258,349,412,352

2[SUP]2[/SUP]

=

4

2[SUP]18[/SUP]

=

262,144

2[SUP]34[/SUP]

=

17,179,869,184

2[SUP]50[/SUP]

=

1,125,899,906,842,624

2[SUP]66[/SUP]

=

73,786,976,294,838,206,464

2[SUP]82[/SUP]

=

4,835,703,278,458,516,698,824,704

2[SUP]3[/SUP]

=

8

2[SUP]19[/SUP]

=

524,288

2[SUP]35[/SUP]

=

34,359,738,368

2[SUP]51[/SUP]

=

2,251,799,813,685,248

2[SUP]67[/SUP]

=

147,573,952,589,676,412,928

2[SUP]83[/SUP]

=

9,671,406,556,917,033,397,649,408

2[SUP]4[/SUP]

=

16

2[SUP]20[/SUP]

=

1,048,576

2[SUP]36[/SUP]

=

68,719,476,736

2[SUP]52[/SUP]

=

4,503,599,627,370,496

2[SUP]68[/SUP]

=

295,147,905,179,352,825,856

2[SUP]84[/SUP]

=

19,342,813,113,834,066,795,298,816

2[SUP]5[/SUP]

=

32

2[SUP]21[/SUP]

=

2,097,152

2[SUP]37[/SUP]

=

137,438,953,472

2[SUP]53[/SUP]

=

9,007,199,254,740,992

2[SUP]69[/SUP]

=

590,295,810,358,705,651,712

2[SUP]85[/SUP]

=

38,685,626,227,668,133,590,597,632

2[SUP]6[/SUP]

=

64

2[SUP]22[/SUP]

=

4,194,304

2[SUP]38[/SUP]

=

274,877,906,944

2[SUP]54[/SUP]

=

18,014,398,509,481,984

2[SUP]70[/SUP]

=

1,180,591,620,717,411,303,424

2[SUP]86[/SUP]

=

77,371,252,455,336,267,181,195,264

2[SUP]7[/SUP]

=

128

2[SUP]23[/SUP]

=

8,388,608

2[SUP]39[/SUP]

=

549,755,813,888

2[SUP]55[/SUP]

=

36,028,797,018,963,968

2[SUP]71[/SUP]

=

2,361,183,241,434,822,606,848

2[SUP]87[/SUP]

=

154,742,504,910,672,534,362,390,528

2[SUP]8[/SUP]

=

256

2[SUP]24[/SUP]

=

16,777,216

2[SUP]40[/SUP]

=

1,099,511,627,776

2[SUP]56[/SUP]

=

72,057,594,037,927,936

2[SUP]72[/SUP]

=

4,722,366,482,869,645,213,696

2[SUP]88[/SUP]

=

309,485,009,821,345,068,724,781,056

2[SUP]9[/SUP]

=

512

2[SUP]25[/SUP]

=

33,554,432

2[SUP]41[/SUP]

=

2,199,023,255,552

2[SUP]57[/SUP]

=

144,115,188,075,855,872

2[SUP]73[/SUP]

=

9,444,732,965,739,290,427,392

2[SUP]89[/SUP]

=

618,970,019,642,690,137,449,562,112

2[SUP]10[/SUP]

=

1,024

2[SUP]26[/SUP]

=

67,108,864

2[SUP]42[/SUP]

=

4,398,046,511,104

2[SUP]58[/SUP]

=

288,230,376,151,711,744

2[SUP]74[/SUP]

=

18,889,465,931,478,580,854,784

2[SUP]90[/SUP]

=

1,237,940,039,285,380,274,899,124,224

2[SUP]11[/SUP]

=

2,048

2[SUP]27[/SUP]

=

134,217,728

2[SUP]43[/SUP]

=

8,796,093,022,208

2[SUP]59[/SUP]

=

576,460,752,303,423,488

2[SUP]75[/SUP]

=

37,778,931,862,957,161,709,568

2[SUP]91[/SUP]

=

2,475,880,078,570,760,549,798,248,448

2[SUP]12[/SUP]

=

4,096

2[SUP]28[/SUP]

=

268,435,456

2[SUP]44[/SUP]

=

17,592,186,044,416

2[SUP]60[/SUP]

=

1,152,921,504,606,846,976

2[SUP]76[/SUP]

=

75,557,863,725,914,323,419,136

2[SUP]92[/SUP]

=

4,951,760,157,141,521,099,596,496,896

2[SUP]13[/SUP]

=

8,192

2[SUP]29[/SUP]

=

536,870,912

2[SUP]45[/SUP]

=

35,184,372,088,832

2[SUP]61[/SUP]

=

2,305,843,009,213,693,952

2[SUP]77[/SUP]

=

151,115,727,451,828,646,838,272

2[SUP]93[/SUP]

=

9,903,520,314,283,042,199,192,993,792

2[SUP]14[/SUP]

=

16,384

2[SUP]30[/SUP]

=

1,073,741,824

2[SUP]46[/SUP]

=

70,368,744,177,664

2[SUP]62[/SUP]

=

4,611,686,018,427,387,904

2[SUP]78[/SUP]

=

302,231,454,903,657,293,676,544

2[SUP]94[/SUP]

=

19,807,040,628,566,084,398,385,987,584

2[SUP]15[/SUP]

=

32,768

2[SUP]31[/SUP]

=

2,147,483,648

2[SUP]47[/SUP]

=

140,737,488,355,328

2[SUP]63[/SUP]

=

9,223,372,036,854,775,808

2[SUP]79[/SUP]

=

604,462,909,807,314,587,353,088

2[SUP]95[/SUP]

=

39,614,081,257,132,168,796,771,975,168

Redagger029 · Jul 8, 2017

Supplied from Answers.com

Day 1: $.01
Day 2: $.02
Day 3: $.04
Day 4: $.08
Day 5: $.16
Day 6: $.32
Day 7: $.64
Day 8: $1.28
Day 9: $2.56
Day 10: $5.12
Day 11: $10.24
Day 12: $20.48
Day 13: $40.96
Day 14: $81.92
Day 15: $163.84
Day 16: $327.68
Day 17: $655.36
Day 18: $1,310.72
Day 19: $2,621.44
Day 20: $5,242.88
Day 21: $10,485.76
Day 22: $20,971.52
Day 23: $41,943.04
Day 24: $83,386.08
Day 25: $167,772.16
Day 26: $335,544.32
Day 27: $671,088.64
Day 28: $1,342,177.28
Day 29: $2,684,354.56
Day 30: $5,368,709.12

The total amount of money, summed over days 1 through day 30 would be:
$10,737,418.23

Bourn · Jul 8, 2017

PatsFan1283 said:
That's not a riddle, it's multiplication.

Yeah you're right. My bad PatsFan. So sorry

festeringZit · Jul 8, 2017

Sigh. None of these answers is correct.

Bourn · Jul 8, 2017

The answer is over $10m

Redagger029 · Jul 8, 2017

festeringZit said:
Sigh. None of these answers is correct.

What is your answer

festeringZit · Jul 8, 2017

HarryCaray said:
Depends on how many days there are in the month.

In a 30 day month you would have over 10 million.

This is a geometric series, the summation as i goes from 0 to # days of 2^i, which the formula is given by : 2^n - 1

28 days: 268,435,455
29 days: 536,870,911
30 days: 1,073,741,823
31 days: 2,147,483,647

Those are in pennies... so HC is correct... my bad

slapshot · Jul 8, 2017

festeringZit said:
This is a geometric series, the summation as i goes from 0 to # days of 2^i, which the formula is given by : 2^n - 1

28 days: 268,435,455
29 days: 536,870,911
30 days: 1,073,741,823
31 days: 2,147,483,647

Those are in pennies... so HC is correct... my bad

hno: