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The number of stamps that Kaye and Alberto had were in the ratio of 5:3 respectively. After Kaye gave Alberto 10 of her stamps, the ration of the number of Kaye had to the number of Alberto had was 7:5. As a result of the gift, Kaye had how many more stamps than Alberto?

The number of stamps that Kaye and Alberto had were in the ratio of 5:3 respectively. After Kaye gave Alberto 10 of her stamps, the ration of the number of Kaye had to the number of Alberto had was 7:5. As a result of the gift, Kaye had how many more stamps than Alberto? (A) […]

The number of stamps that Kaye and Alberto had were in the ratio of 5:3 respectively. After Kaye gave Alberto 10 of her stamps, the ration of the number of Kaye had to the number of Alberto had was 7:5. As a result of the gift, Kaye had how many more stamps than Alberto? Read the Full Article »

The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A

The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A. GMAT Explanation, Video Solution, and Additional Practice! The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A present and inversely proportional to the concentration of chemical B

The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A Read the Full Article »

A vending machine is designed to dispense 8 ounces of coffee into a cup. After a test that recorded the number of ounces of coffee in each of 1000 cups dispensed by the vending machine, the 12 listed amounts, in ounces, were selected from the data above. If the 1000 recorded amounts have a mean of 8.1 ounces and a standard deviation of 0.3 ounces, how many of the 12 listed amounts are within 1.5 standard deviation of the mean?

7.51 8.22 7.86 8.36 8.09 7.83 8.30 8.01 7.73 8.25 7.96 8.53 A vending machine is designed to dispense 8 ounces of coffee into a cup. After a test that recorded the number of ounces of coffee in each of 1000 cups dispensed by the vending machine, the 12 listed amounts, in ounces, were selected

A vending machine is designed to dispense 8 ounces of coffee into a cup. After a test that recorded the number of ounces of coffee in each of 1000 cups dispensed by the vending machine, the 12 listed amounts, in ounces, were selected from the data above. If the 1000 recorded amounts have a mean of 8.1 ounces and a standard deviation of 0.3 ounces, how many of the 12 listed amounts are within 1.5 standard deviation of the mean? Read the Full Article »

The number 75 can be written as the sum of the squares of 3 different positive integers. What is the sum of these 3 integers?

The number 75 can be written as the sum of the squares of 3 different positive integers. What is the sum of these 3 integers? (A) 17 (B) 16 (C) 15 (D) 14 (E) 13 This question is from the free official GMAT practice tests 1 and 2 so avoid if you haven’t done those

The number 75 can be written as the sum of the squares of 3 different positive integers. What is the sum of these 3 integers? Read the Full Article »