Savings- Suppose that every day you save twice as many pennies as you saved the day before. You start by saving once penny on January 1. How much money will have in all on January 10?

Question

anonymous · Answer

10.23

yanasidlinskiy · Answer

Mind explaining, Aydia?

anonymous · Answer

Sure. 
The first day, you save 0.01 cents. That, times, two, is 0.02 on January 2nd. That times two is 0.04 on January 3rd. I'll write the rest of the pattern. 
0.04 x 2 = 0.08 on January 4th
0.08 x 2 = 0.16 on January 5th
0.16 x 2 = 0.32 on January 6th 
0.32 x 2 = 0.64 on January 7th 
0.64 x 2 = 1.28 on January 8th 
1.28 x 2 = 2.56 on January 9th 
2.56 x 2 = 5.12 on January 10th 

Add all of the results together. 
0. 01 + 0.02 + 0.04 + 0.08 + 0.16 + 0.32 + 0.64 + 1.28 + 2.56 + 5.12 = 10.23

No, I don't know the actual formula for it. I wasn't a top algebra student. But I can logic my way through almost all of the problems.

anonymous · Answer

Thanks, if i ever stuck on a problem i'll let you know