16% of 231 is 36.80
16% + 84% = 100%
36.80+ 231 = $267.80
Ans = $267.80
|4r + 8| ≥ 32
Split this expression into two expressions:
First ⇒ 4r + 8 ≥ 32 and second ⇒ 4r + 8 ≤ - 32
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First expression: 4r + 8 ≥ 32
Subtract 8 from both sides.
4r ≥ 24
Divide both sides by 4.
r ≥ 6
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Second expression: 4r + 8 ≤ - 32
Subtract 8 from both sides.
4r ≤ -40
Divide both sides by 4.
r ≤ -10
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Your answer is 
Since she flipped the coin 20 times and got 4 heads and 6 tails, you put it as a fraction. So, it's 4/16 if you simplify 4 over 16 you get 1/4. You get this by dividing by 4 both numbers.
1) $600 deposited at 4% simple interest for one year generates:
$600 * 4% = $600 * 0040 = $24
2) If he wants to earn $132 in interest for the year, he yet needs to generate $132 - $24 = $108 (additional)
3) The interest rate to generate $108 on a deposit of $1200 in a year, at simple interest is:
$1200 * (r) = $108 => r = 108 / 1200 = 0.09 = 9/100 = 9%
Answer: 9%
