HOMEWORK #1 [MATH 55(31) WD SMITH] ANSWERS
PERFECT SCORE = 60/60
p217 sec 4A of book, #1,3,5,7,13,25.

1. x-4=6   (add 4 to both sides) x=10
   y+5=10  (-5 to both sides) y=5
   2z=12   (/2 to both sides) z=6
   3z=15   (/3 to both sides) z=5
   2x-5=13 (+5 to both sides then /2) x=9
   3n+4=13 (-4 then /3) n=3
   4x+8=24 (-8 then /4) n=4
   5-2w=9 (-5 then divide by 2 then negate) w=-2.

3. Yancy starts $500, 5% simple interest for 5 years, final balance
   $625.  This is $125 increase, and 125/500=0.25=25% fractionally.

Samantha using compound interest ends up with $638.14.
This is $138.14 increase which fractionally is 138.14/50=0.276=27.6%
increase.
                                                10
5. $2000 at APR of 3%, 10 years, get 2000*(1.03)  = $2687.83.

                                                  20
7. $30000 at APR=7% for 25 years, get 30000*(1.07)   = $162822.98.


13. $1000, APR=5.5%, compound monthly, 10 years, get

                   120
1000*(1 + 0.055/12)   = $1731.08.


25. Invest $1000 for 1 year at APR=6.6% (compounded quarterly)
then end up with            4
          1000*(1 + 0.066/4) = $1067.65    1 year later.
So APY = annual percentage yield = 67.65/1000 = 0.06765 = 6.77%.

If compounding is monthly, then end up with
                             12
          1000*(1 + 0.066/12)   = $1068.03    1 year later.
So APY = annual percentage yield = 68.03/1000 = 0.06803 = 6.80%.

If compounding is daily, then end up with
                             365
          1000*(1 + 0.066/365)   = $1068.22    1 year later.
So APY = annual percentage yield = 68.22/1000 = 0.06822 = 6.82%.