GMAT Math

1- It took carlos 1/2 hr to cycle from his house to library, was the distance that he cycled greater than 6 miles?

a- Avg speed was greater than 16 ft/sec.
b- Avg speed was less than 18ft/sec.

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2- for each of her sale, a sales woman receives 20% of the first $500 of the total amount of the sale, plus 30% of the total amount of the sale in excess of $500. if the total amount of one of her sales was $800, the saleswoman comission was approx what percent of the total amount of sales?
22% 24% 24% 27% 28%

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3- Alice's take home-pay last year was the same ewach month, and she saved the same fraction of the pay each month. the total amount of moiney she had saved at the end of the year was3 times the amount of that portion of monthly pay that she didnot save . if all the money that she saved last year was from her pay, waht fraction of her pay did she save each month?

1/2 1/3 1/4 1/5 1/6

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4- during a 1 day sale, o store sold each sweater of a certain type for $30 more than the store's cost to purchase each sweater. how many of these sweaters were sold during the sale?

a- during the sale, the total revnue from the sale of these sweaters wes $270.
b- during the sale, the store sold each of these sweaters at a price that was 50 percent greater than the store's price to purchase them.


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question 4

regarding the first information: x+30$=price per sweater
y- number of sweaters. (x+30)y=270
therefore 1- not sufficient to answer

second statement: 30*50%=15$
price per swater=15+30=45$

if using the first statement total cash from sweaters- 270
270/45=6

therefore both statements are needed to solve

3- Alice's take home-pay last year was the same ewach month, and she saved the same fraction of the pay each month. the total amount of moiney she had saved at the end of the year was3 times the amount of that portion of monthly pay that she didnot save . if all the money that she saved last year was from her pay, waht fraction of her pay did she save each month?

1/2 1/3 1/4 1/5 1/6

lets assume y is part that she saved each month
x whole salary , x-y part that she did not save
12y=3(x-y)
12y=3x-3y
15y=3x x=5y

therefore the answer is 1/5 th

to check: assume salary was 500 $
she saves 1/5- 100$. in twelve months 1200
wich is 3 times the amount she didnt ssave 400*3

2- for each of her sale, a sales woman receives 20% of the first $500 of the total amount of the sale, plus 30% of the total amount of the sale in excess of $500. if the total amount of one of her sales was $800, the saleswoman comission was approx what percent of the total amount of sales?
22% 24% 24% 27% 28%


if total is 800, lets divide it into 500 and 300 that was in excess of 500$
for 500 usd sale she received 20% commision = 500*20%=100$
then she sold 300 more and recieved comission 30%=90%

190$ total comission
190 is 23.75% of 800

so probably answer is 24% apporximately

Q1. The best way to work this problem would be to:

1. convert your speed from ft/sec to ft/min
2. calculated the distance travel for a & b as a reference point
3. choose a value in the middle, then calculate distance traveled.
4. Compare and make a decision

This will make the comparison easier, and 1mile = 5280ft, but you can always approximate 1 ~ 5,000 feet

Therefore 6 miles = 31,620 ft, So you are looking for which value will give you this.

Now calculate the distance traveled for the the time given (1/2 hr = 30min)

a. > 16ft/sec = (16ft/sec) (60sec/1mim) => 960 ft/min
Distance traveled @ 16ft/sec => 28,800 feet
b. < 18ft/sec = (18ft/sec) (60sec/1mim) => 1080 ft/min
Distance traveled @ 18ft/sec => 32,400 feet


a. Speed > 16ft/sec , so this can be 16.1 ft/sec or more (take 17ft/sec ==> 30,600 feet traveled, you would not have traveled 6 miles, but if your value is larger than 17.6ft/sec + you would have traveled 6 miles.

b. Speed < 18ft/sec , so this can be 17.9 ft/sec or less (for certain values you would be above or below six miles). With 17.9ft/sec that would be yes, but at 17ft/sec the person would not have traveled six miles.


In both cases it would be NO because there is no additional information given to help you zero in on a answer, such as average speed must be an integer. Or average speed is not an integer.

Thank you for ur explanation. Your answers r right.