A couple dining at a restaurant receives a bill for $28.40. They wish to leave a 10% tip. Which of the following is the estimated gratuity?

We are needed to find the amount Jacob will be left with after spending and reinvesting the rest using the given information.

Amount Jacob spends=87% of $100=87/100*100=$87

Amount left to invest=$(100-87)=$13

Jacob is left with $13, which she invests and earns a profit of 75%.

Profit earned on invested amount=75% of $13=75/100*13=$9.75

So, Jacob will have $13+$9.75=$22.75

from the given data, one gallon of cleaning solution requires 6 oz of ammonia. The mathematical expression of this statement can be expressed in two ways:

Or

The question requires we find the amount of ammonia needed to make 230 gallons of the solution. So, we use the second option and proceed as follows:

From the above equation, gallon of solution will cancel, and oz of ammonia is left.

Therefore, the solution will require 1380 oz of ammonia.

We know that 1 L =1000 mL, which we use 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, 3.2 L is equivalent to 3200 mL.

 we are to find the selling price of the sweater from the marked price and the discount. The marked price is given as

Discount=mark off rate*original price

Discount=15%*$78

Convert 15% into a fraction, which become 15/100=0.15. Then

Discount=0.15*$78=$11.70

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

Thus, the approximate selling price of the sweater is $66.

: the question requires we find the cost of four syringes.

If we let x be the cost of four syringes, then we set up a proportion equation with cost as numerator and number of syringes as denominator. The proportion equation becomes

Cross-multiply to solve for x

Rearranging the above

Divide both sides of the equation by 55

Thus, the cost of 4 syringes is $48.

correlations fall into positive, negative, and no correlation. A positive correlation shows that an increase in one variable increase results in an increase on the other variable increases as shown.

A negative correlation scatter plot shows that an increase in one variable results in a decrease on the other one.

The no-correlation scatter plot demonstrates that there is no response between variables. A change in one variable has no effect on the other variable.

Looking at the provided scatter plot, the heights of the students does not have any relationship on the students’ scores. Thus, the type of correlation is no correlation.

to convert fraction to percent, multiply the fraction with 100%. Therefore, the percent equivalent of 3/4 is

3/4*100%=75%

Thus, 3/4is equal to 75%.

: we are needed to find the portion of burger the two other friends share between themselves. A whole burger is 1, and we know that,

One friend=1/4 of 1=1/4*1=1/4

Remaining amount=1-1/4=4/4-1/4=3/4

Thus, ¾ of burger is left for two friends to share among themselves. Then, each friend will get

So, the other two friends will each get 3/8 of the burger.

We need to find the radius in order to find the area of the pizza.

Radius of pizza

The area of the pizza

But r=4.5

Thus, the area of the pizza is 20.25  in2.

NOTE:  is used as is since values of pi may vary e.g. 3.14, 3.142, 22/7. Hence we use pi symbol to generalize.

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 two times width. Mathematically, this means

Length=2*width=2*x=2x

Now, the length is 6 less than 2 times width of the rectangle. Thus, the length of rectangle in terms of width becomes:

Length =2x-6

Thus, the length of the rectangle is 2x-6.