SAT Mathematics : Divisibility & Number Fluency

Study concepts, example questions & explanations for SAT Mathematics

varsity tutors app store varsity tutors android store varsity tutors amazon store varsity tutors ibooks store

Example Questions

← Previous 1 3. 4

Example Question #1 :Divisibility & Number Fluency

Jesse has a large movie collection containingmovies.of his movies are action movies,of the remainder are comedies, and the rest are historical movies. How many historical movies does Jesse own?

Possible Answers:

Correct answer:

Explanation:

of the movies are action movies.ofof the movies are comedies, or, or. Combining the comedies and the action movies (or), we getof the movies being either action or comedy. Thus,of the movies remain and all of them have to be historical.

Example Question #2 :Divisibility & Number Fluency

Ifand, find the value of.

Possible Answers:

Correct answer:

Explanation:

Substitute the values ofandinto the given expression:

Example Question #3 :Divisibility & Number Fluency

Let the nth term of a sequence be denoted asand given by the following equation:

For example, the tenth term of the sequence is.

What is the sum of the first five terms of the sequence?

Possible Answers:

Correct answer:

Explanation:

In order to find the sum of the first five terms, we will need to find the values of each of the first five terms using the equation given above. Essentially, we will letrange fromtoto determine each term.

Remember that anything to the power of zero is equal to 1. Therefore,raised to the zero power is also.

In general, whenis raised to an even power, the result is. Conversely, ifis raised to an odd power, the result is.

Thus, the first five terms of the sequence are. We must now add these all together. Because we are adding fractions with unlike denominators, we need to find the smallest multiple thathave in common. Becauseis a multiple of, we really only need to worry about. If we were to list out the multiple of, e would see that the smallest one they have in common is. Sometimes, the easiest way to find the least common multiple of several numbers is o multiply them together. The products ofis.

We will now convert each fraction to an equivalent form with a denominator of. For example, if we were to convertto a fraction with a denominator of, we would multiple both the numerator and denominator by, as shown below:

The answer is.

Example Question #1 :Working With Fractions

What is the solution, reduced to its simplest form, forx = \frac{7}{9}+\frac{3}{5}+\frac{2}{15}+\frac{7}{45}}?

Possible Answers:

Correct answer:

Explanation:

Example Question #5 :Divisibility & Number Fluency

What is the result of addingofto?

Possible Answers:

Correct answer:

Explanation:

Let us first get our value for the percentage of the first fraction.ofis found by multiplyingby(or, simplified,):

Our addition is therefore. There are no common factors, so the least common denominator will beor. Multiply the numerator and denominator ofbyand the numerator ofby

This yields:

, which cannot be reduced.

Example Question #6 :Divisibility & Number Fluency

Add:

Possible Answers:

Correct answer:

Explanation:

Find the least common denominator to solve this problem

Multiply 27 with, and multiplywith 3 to obtain common denominators.

Convert the fractions.

Combine the terms as one fraction.

The answer is:

Example Question #7 :Divisibility & Number Fluency

A record store has stocked up on new supplies so that their current inventory consists of pop, rock, and hip-hop.of their records are pop records andof their records are rock records. If the store has a total ofrecords, how many hip-hop records are stocked in the store?

Possible Answers:

Correct answer:

Explanation:

首先,我们必须找到嘻哈的分数记录s are there in the store. We find a common denominator for the faction of pop records and rock records by multiplyingbyandbyto getrecords being pop records andrecords being rock records.

In order to get the faction of hip-hop records remaining in the store, we must write out:

since the sum total of the fractions must add up to. We solve to get.

This tells us that fraction of hip-hop records must be.

The question is asking how many records are stocked in the store, therefore we need a denominator of. We can write outand solve for.

Similarly, this question can be solved using deduction. Ifofisandofis, knowing that we need the amount remaining, we can subtractfromand get.

Answer choiceis wrong because it is finding the total amount of Pop records.

Answer choiceis wrong because it is finding the total amount of rock records.

Answer choiceis wrong because the factions were added incorrectly.

Example Question #8 :Divisibility & Number Fluency

Jackson wrote a song with equal parts pre-chorus, chorus, and bridge. The song ends up beingminutes andseconds with a beat occurring everyseconds. How many beats are there in the chorus?

Possible Answers:

Correct answer:

Explanation:

First, we must convert the song length from minutes and seconds to simply seconds.
. We addseconds toseconds and getseconds total song length.

If the song is equal parts pre-chorus, chorus, and bridge that meansof the song is composed of pre-chorus,of the song is composed of chorus, andof the song is composed of bridges. Therefore, we dividebyand getseconds of chorus.
Since a beat occurs every five seconds, we divideseconds byseconds to get the amount of beats in that time frame.. Since a beat can not be sectioned, the answer is rounded down to.

Answer choiceis incorrect because it is finding the total number of beats in the song.

Answer choiceis incorrect because it rounds up to the nearest beat.

Example Question #2 :Sat Math

Please simplify the following:

Possible Answers:

Correct answer:

Explanation:

The rule for dividing fractions is invert the second fraction and multiply. We keep theas it is then change the division sign to a multiplication sign and invertinto.
becomes.

Similarly, you can memorize, “top, bottom, bottom, top” meaningis on top and it stays on top,is labeled bottom and it stays on the bottom,is labeled bottom and it moved to the bottom, thenis labeled top so it moves to the top.

Example Question #10 :Divisibility & Number Fluency

找到的价值if

Possible Answers:

Correct answer:

Explanation:

To find the answer we must cross multiply. When we cross multiply we get:

or

We subtractfrom

Then we solve for x by dividing by 6,


← Previous 1 3. 4
Learning Tools by Varsity Tutors