Really Need help with this problem!!!!!!

Question

Every day Sally saved a penny, a dime, and a quarter. What is the least number of days required for her to save an amount equivalent to an integral number of dollars?

Answer 1

Al pal,

   Sally is saving 36 cents daily.  We want her to save an integral number of dollars, which means the number of cents must be a multiple of 100.  So, we need to find the least common multiple of 36 and 100.  An easy way to do this is test each multiple of 100 to see if it is divisible by 36.  The quotient must be a whole number when we divide.

 

100/36 = 2.77  NO

200/36 = 5.56 NO

300/36 = 8.33  NO

400/36 = 11.11 NO

500/36 = 13.89  NO

600/36 = 16.67  NO

700/36 = 19.44 NO

800/36 = 22.22  NO

900/36 = 25  YES!

 

So, if Sally saves a penny, dime, and quarter each day for the next 25 days she will have 900 cents, which is $9.

 

Hope this helps!

 

Gordon

Answer 2

1 penny+10 pennies+25 pennies=36 pennies

36=2*2*3*3

you want a multiple of 100 that is divisible by 3*3; any multiple of 100 is divisible by 2*2

the multiple of 100 you want is 900, or $9.00

900/36=25 days

check:36,72,108,144,180,216,252,288,324,360,396,432,468,504,540,576,612,648,684,720,756,792,828,864,900