Aniya saved $5 per month in a bank account for 4 1/2 years. She spent 20% of her savings on a new watch. How much did Aniya have left in her account?

$216

Step-by-step explanation:

lets convert 4.5 years into months

4.5 years= 54 months

so Aniya saved $5 per month, for 54 months

lets take m as the # of months

5m->5(54)

5(54)=270

Aniya has $270 in her savings. Then she spent 20% of it on a watch

so

0.2*270=54

20% of 270 is 54 so

270-54=216

Aniya has $216 left

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)