Answer:
Distributive property
Step-by-step explanation:
The five was distributed to the 3 and the v
They added it wrong. They added it like this:
When it shouldve been this:
They just added a place marker in all numbers below 100.
A factor pair is two numbers that can be multiplied to get a number.
With any number, we know that 1*itself is a factor pair. So
1*64
The number in the ones place, 4, is even, so we know that 64 is a multiple of 2. Half of 64 is 32, so
2*32
To find out if 3 is a factor of 64, we can add 6+4. If the answer is a multiple of 3, then we know that the number itself is a multiple of 3. Because 6+4=10, and 10 is not a multiple of 3, we know that 64 is not a multiple of 3.
If 2 is not a factor of a number, then we know that 4 (2*2) cannot be a factor. Because 2 is a factor of 64, then 4 might be as well. To discover whether or not 4 is a factor of 64, we can look at the number above multiplied by 2 to equal 64 (32) and see if it divides by 2 evenly, or we can half 64 and then half it again. If either answer is a whole number, then we know that the answer*4 equals 64, and that 64 is a multiple of 4. Because half of 32 is 16, a whole number, we know that
4*16=64
Because 64 does not have a 0 or 5 in the one's place, we know that it cannot be a multiple of 5.
Because 64 is not a multiple of 3, we know it cannot be a multiple of 6, because 6 is 2*3.
I happen to be familiar with my times tables, so I can tell that the multiples of 7 are 63 and 70, but not 64.
I don't know if 64 is a multiple of 8 off the top of my head, but I can count by 8s and see if 64 comes up: 8, 16, 24, 32, 40, 48, 56, 64, 72 - I can go on, but we can already see that 64 is a multiple of 8, so 8 is a factor of 64. If we count the number of 8s I can see that there are 8 of them when we get to 64. In other words,
8*8=64
Because we have gotten to a factor pair that is the same 2 number multiplied by each other (the square root) we know that we have found all factor pairs of 64.
Answer:
8 records were sold on Wednesday, and 24 records were sold on Thursday
Step-by-step explanation:
Let's call the number of records sold on Wednesday w, and the number sold on Thursday t.
t+w=32
t=3w
Substituting:
(3w)+w=32
4w=32
w=8
t=3w=3(8)=24
Hope this helps!
Answer:
Almost 2.5% of the students spent more than $275 in a semester.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 235
Standard deviation = 20
According to the standard deviation rule, almost 2.5% of the students spent more than what amount of money on textbooks in a semester?
95% of the measures are within 2 standard deviation of the mean. The other 5% are more than 2 standard deviations of the mean. Since the normal distribution is symmetric, 2.5% of those are below two standard deviations of the mean and 2.5% are more than two standard deviations above the mean.
235 + 2*20 = $275
Almost 2.5% of the students spent more than $275 in a semester.
