Option B:
The expression equivalent to |a| ≤ 5 is a ≥ -5 and a ≤ 5.
Solution:
Given expression: 
To find the equivalent expression for the given expression.
Apply absolute value rule:
<em>If |x| ≤ m then -m ≤ x ≤ m.</em>
⇒ -5 ≤ a ≤ 5
⇒ -5 ≤ a and a ≤ 5
Switch the sides, we get
⇒ a ≥ -5 and a ≤ 5
The expression equivalent to |a| ≤ 5 is a ≥ -5 and a ≤ 5.
Option B is the correct answer.
Answer: $222.73
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Work Shown:
x = pre-GST price
10% of x = 0.10x = tax amount
x + 0.10x = 1.10x = post-GST price = 245
1.10x = 245
x = 245/1.10
x = 222.7272 approximately
x = 222.73 is the price before tax.
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Check:
10% of 222.73 = 0.10*222.73 = 22.273 = 22.27
The tax amount ($22.27) is added to the pre-GST price to get
22.27+222.73 = 245
which matches the post-GST price mentioned.
The answer is confirmed.
Or another way to confirm the answer is to calculate this
1.10*222.73 = 245.003 = 245
You would use cross multiplication:
X/2,000 = 3/5
Multiply: 2,000*3= 6,000
Divide: 6,000/5
Answer: 1,200 doctors use brand x
George shouldn't think too far.
He should use the formula for Compound Interest.
Amount in compound interest, A = P(1+ r/100)ⁿ.
Where A = Amount, P = Principal, r is the rate per year, n = number of years.
Note: the expression (1+ r/100) is raised to power n.
From George's problem: P = 750, r = 22, I guess number of years , n = x
A(x) = 750( 1 + 22/100)ˣ
A(x) = 750( 1 + 0.22)ˣ
From your options I can't see an answer. Except the expression of option (A) is actually raised to power x, and not times x as stated in the option.
