A couple dining at a restaurant receives a bill for $38.40. They wish to leave a 15% gratuity. Which of the following is the estimated gratuity?

we are needed to find the amount Lana is left with after spending and investing the rest using the given information.

Amount Lana spends = 80% of $60= 80/100 *60 = $48

Amount left to invest = $(60-48) = $12

Lana is left with $12, which she invests and earns a profit of 80%.

Profit earned = 80% of $12 = 80/100 * 12= $9.20

So, Lana will have $12 + $9.20 = $21.60

we follow the order operations to solve for the unknown value of x.

2(4x+3)=7x+5

Open the bracket on the LHS by multiplying each term by 2

(2*4x)+(2*3)=7x+5

8x+6=7x+5

Subtract 6 from both sides

8x+6-6=7x+5-6

8x=7x-1

Subtract 7x on both sides

8x-7x=7x-7x-1

X=-1

Thus, the value of unknown value of x is -1.

We are told to find the area of the pizza given its diameter. The pizza is in circular form, and its area is found as:

However, we are not given r, which is the radius of the circle. But we can find it from the given diameter as

Substituting r=8 in the equation of the area of a circle

Thus, the area of the pizza is 64  in2.

NOTE:  (Pi) remains as a symbol because values of Pi can vary from 22/7 to 3.1415 to 3.14 and so forth.

we are needed to find the portion of pizza shared by 3 three friends. We treat the whole pizza as 1. Now, 1 friend eats half of the whole pizza. Thus,

One friend=1/2 of 1=1/2*1=1/2

Remaining amount=1-1/2=2/2-1/2=1/2

Thus, ½ of pizza is left for three friends to share among themselves. Then, each friend will get

So, the other three friends will each get 1/6 of the pizza.

the median of a data set is the element that is found on the middle position. It is found by organizing the elements from the smallest to largest.

The data set above arranged from the smallest to largest is:

11, 12, 12, 12, 13, 14, 17, 17, 18, 22, 26

The number of elements is odd and the median is found in the (N+1)/2 th position. Here N=11, and the median falls in (11+1)/2=12/2=6 th position.

The element 14 falls in the 6th position, which is our median of the given data set.

: we are to find the selling price of the sweater after subtracting the mark off price.

Mark off value=mark off rate*original price

Mark of value=25%*$87

We convert 25% into a fraction, which become 25/100=0.25. Then

Mark of value=0.25*$87=$21.75

The selling price of the sweater will be the original price less the mark off value. Then,

Thus, the approximate selling price of the sweater is $65.

We use 1 L =1000 mL to convert between the two units. The conversion fractions of interconverting are:

And

Since we want to end up with millimeters, the second conversion is used in converting L to mL as:

Thus, 0.5 L is equivalent to 500 mL.

a ratio can be converted to a fraction of the form a/b, where b is not equal to zero. In ratio form, to means per.

From the given information, the class has 15 girls and 13 boys. Thus, the ratio of girls to boys becomes:

In ratio form, girls: boys=15:13

Thus, the ratio of girls to boys in a class of 28 students is 15 to 13.

To form an equation from the word problem, first break the given statement into smaller statements.

First, we are given the width of the rectangle as x. We are told, the length is three times width. Mathematically, this means

Length=3*width=3*x=3x

Again, the length is 4 less than 3 times width of the rectangle. Thus, the length of rectangle in terms of width becomes:

Length =3x-4

This is the required equation.

The initial step is to convert the decimal numbers into fractions.

4.4 becomes 44/10

4.25 becomes 425/100

Thus, the set of fractions is 9/2, 44/10, 10/3, 425/100. The least common denominator for 2, 10, 3, and 100 is 300, which we use to compare each options given.

9/2*300=1350

44/10*300=1320

10/3*300=1000

425/100*300=1275

From the above, 1350 is the greatest value which corresponds to 9/2. Thus, 9/2 is the greatest value of all the choices given.