If she deposited $600 and had $621.60 after four years, then she earned: $621.60 - $600 = $21.60 in four years. It means in one year she earned $21.60 ÷ 4 = $5.40. Now we have to find out how many percent of $600 is $5.40:
$5.40 = x% from $600
5.4 = x/100 * 600
5.4 = 600x/100 / * 100 (both sides)
540 = 600x / ÷ 600 (both sides)
x = 0.9
So the interest rate was 0.9% annually.
Now we have to find out how much is 0.9% from $1100:
$1100 * 0.9% =
= 1100 * 9/1009 =
= 9900/1000 =
= 9.9
It means in one year she would earn $9.90. After 7 years she would earn $9.90 * 7 = $69.30, so she would have in her account:
$1100 + $69.30 = <u>$1169.30</u>
The unknown number expressed as a mixed fraction is 11 19/20
Let the unknown number be "x"
The sum of the number and 1.75 is expressed as x + 1.75
Half the sum of a number and 1.75 is 1/2(x+1.75)
Equating the result to -5.1 wil give:
1/2(x+1.75) = -5.1
Solve the resulting equation
x + 1.75 = 2(-5.1)
x + 1.75 = -10.2
x = -10.2 - 1.75
x = 11.95
x = 1195/100
x = 11 95/100
Hence the unknown number expressed as a mixed fraction is 11 19/20
Learn more here: brainly.com/question/14583740
C
because you just eliminate it