How to find the missing number in a set - SAT Math
Card 0 of 9
Which number completes the following series: 1, 2, 4, 8, 16, 32, 64, _?
Which number completes the following series: 1, 2, 4, 8, 16, 32, 64, _?
All of the numbers in this series are 2n-1. The number that we are looking for is the eighth number. So 28–1 = 27 = 128.
All of the numbers in this series are 2n-1. The number that we are looking for is the eighth number. So 28–1 = 27 = 128.
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Alhough Danielle’s favorite flowers are tulips, she wants at least one each of three different kinds of flowers in her bouquet. Roses are twice as expensive as lilies and lilies are 25% of the price of tulips. If a rose costs $20 and Danielle only has $130, how many tulips can she buy?
Alhough Danielle’s favorite flowers are tulips, she wants at least one each of three different kinds of flowers in her bouquet. Roses are twice as expensive as lilies and lilies are 25% of the price of tulips. If a rose costs $20 and Danielle only has $130, how many tulips can she buy?
She can only buy 2 tulips at $80, because if she bought 3 she wouldn’t have enough to afford the other 2 kinds of flowers. She has to spend at least 30 dollars (20 + 10) on 1 rose and 1 lily.
She can only buy 2 tulips at $80, because if she bought 3 she wouldn’t have enough to afford the other 2 kinds of flowers. She has to spend at least 30 dollars (20 + 10) on 1 rose and 1 lily.
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Find the missing number in the following set:
Find the missing number in the following set:
The rule is as follows: add 2 to the previous number then multiply times 2.
The answer is (16 + 2) * 2 = 36.
The rule is as follows: add 2 to the previous number then multiply times 2.
The answer is (16 + 2) * 2 = 36.
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Which of the following is not a rational number?
Which of the following is not a rational number?
A rational number is a number that can be written in the form of a/b, where a and b are integers, aka a real number that can be written as a simple fraction or ratio. 4 of the 5 answer choices can be written as fractions and are thus rational.
5 = 5/1, 1.75 = 7/4, .001 = 1/1000, 0.111... = 1/9
√2 cannot be written as a fraction because it is irrational. The two most famous irrational numbers are √2 and pi.
A rational number is a number that can be written in the form of a/b, where a and b are integers, aka a real number that can be written as a simple fraction or ratio. 4 of the 5 answer choices can be written as fractions and are thus rational.
5 = 5/1, 1.75 = 7/4, .001 = 1/1000, 0.111... = 1/9
√2 cannot be written as a fraction because it is irrational. The two most famous irrational numbers are √2 and pi.
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Which set represents all the single-digits integers (0-9) that are either prime, a perfect square, or found in the number 68?
Which set represents all the single-digits integers (0-9) that are either prime, a perfect square, or found in the number 68?
The prime digits are 2, 3, 5, and 7.
The perfect square digits are 0, 1, 4, and 9.
The only digits not represent in these two groups are 6 and 8, which are, coincidentally, found in the number 68.
The prime digits are 2, 3, 5, and 7.
The perfect square digits are 0, 1, 4, and 9.
The only digits not represent in these two groups are 6 and 8, which are, coincidentally, found in the number 68.
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If four different integers are selected, one from each of the following sets, what is the greater sum that these four integers could have?
W = {4, 6, 9, 10}
X = {4, 5, 8, 10}
Y = {3, 6, 7, 11}
Z = {5, 8, 10, 11}
If four different integers are selected, one from each of the following sets, what is the greater sum that these four integers could have?
W = {4, 6, 9, 10}
X = {4, 5, 8, 10}
Y = {3, 6, 7, 11}
Z = {5, 8, 10, 11}
By observing each of these sets, we can easily determine the largest number in each; however, the problem is asking for us to find the greatest possible sum if we select four different integers, one from each set. The largest number is 11. We will either select this number from set Y or set Z.
We will select set
Y for the 11
because the next larger number in set
Z is 10, which is greater than the next largest number is set Y, 7.
We can use set Z for 10.
Because the 10 has already been selected, choosing the integer from W and X should be easy because 9 is the next largest integer from set W
and
8 is the next largest integer from set X.
11 + 10 + 9 + 8 = 38
By observing each of these sets, we can easily determine the largest number in each; however, the problem is asking for us to find the greatest possible sum if we select four different integers, one from each set. The largest number is 11. We will either select this number from set Y or set Z.
We will select set
Y for the 11
because the next larger number in set
Z is 10, which is greater than the next largest number is set Y, 7.
We can use set Z for 10.
Because the 10 has already been selected, choosing the integer from W and X should be easy because 9 is the next largest integer from set W
and
8 is the next largest integer from set X.
11 + 10 + 9 + 8 = 38
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A team has a win-loss ratio of 
. If the team wins six games in a row, the win-loss ratio will now be 
. How many losses did the team have initially?
A team has a win-loss ratio of
If a team's ratio of wins to losses increases from 
to 
by winning six games, they must have 12 wins initially and 3 losses.
If a team's ratio of wins to losses increases from
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You have the following data set:
.
Find the missing number 
in the data set.
You have the following data set:
Find the missing number
In order to find the missing number (X), you must first identify the pattern in the set of numbers. Upon a glance, you can determine that the pattern starts with 4 and then the next number is 2n+1, with n being the preceding number in the set.
For example, let's start with 4. Multiplying 2*4+1 gives us 9, the next number in the set.
Therefore, the missing number in the set is 
.
In order to find the missing number (X), you must first identify the pattern in the set of numbers. Upon a glance, you can determine that the pattern starts with 4 and then the next number is 2n+1, with n being the preceding number in the set.
For example, let's start with 4. Multiplying 2*4+1 gives us 9, the next number in the set.
Therefore, the missing number in the set is
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A sequence of boxes is constructed, the first six of which are seen above. What number is in the lower right corner of the ninth box?
A sequence of boxes is constructed, the first six of which are seen above. What number is in the lower right corner of the ninth box?
The lower right number of each box is the sum of the other three numbers, which are found as follows:
The upper left numbers are simply the natural numbers in order;
The upper right numbers are the powers of 2, beginning with 
;
The lower left numbers are the terms of the Fibonacci sequence, which is formed by setting the first two terms equal to 1 and each subsequent term equal to its predecessors.
Therefore, the ninth box in the sequence includes the number 9 as its upper left entry, and 
as its upper right entry. The lower left entry is the ninth Fibonacci number, which can be found as follows:
The lower right entry is the sum of the other entries:
The lower right number of each box is the sum of the other three numbers, which are found as follows:
The upper left numbers are simply the natural numbers in order;
The upper right numbers are the powers of 2, beginning with
The lower left numbers are the terms of the Fibonacci sequence, which is formed by setting the first two terms equal to 1 and each subsequent term equal to its predecessors.
Therefore, the ninth box in the sequence includes the number 9 as its upper left entry, and
The lower right entry is the sum of the other entries:
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