1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Evgen [1.6K]
3 years ago
11

How can 400x20 help solve 399x20

Mathematics
2 answers:
jeka57 [31]3 years ago
7 0
Just subtract 20 from the answer of 400x20. One number less.
Dvinal [7]3 years ago
5 0
What you can do is multiply 400*20= 8,000. From here, we know that 399*20 is just one less group of 20 than 400. Therefore, we can subtract (1*20) from 8,000 to get the final answer.

8000-20=7980

Hope this helps!
You might be interested in
30 points for RIGHT ANSWER
juin [17]
The answer is 18 I’m pretty certain so D
8 0
3 years ago
√180 can be expressed in the form p√q. where p and q are integers. Find the smallest value of p + q. ​
frutty [35]

Answer:  

The smallest value of p+q is 11

It happens when p = 6 and q = 5.

=======================================================

Explanation:

Let's factor 180 in such a way that exactly one factor is a perfect square.

I'll ignore the trivial factor of 1.

Here are the possible factorizations we could go with:

180 = 4*45

180 = 9*20

180 = 36*5

Those factorizations then lead to the following

\sqrt{180} = \sqrt{4*45} = \sqrt{4}*\sqrt{45}= 2\sqrt{45}\\\\\sqrt{180} = \sqrt{9*20} = \sqrt{9}*\sqrt{20}= 3\sqrt{20}\\\\\sqrt{180} = \sqrt{36*5} = \sqrt{36}*\sqrt{5}= 6\sqrt{5}\\\\

Then we have

p+q = 2+45 = 47

p+q = 3+20 = 23

p+q = 6+5 = 11

The smallest value of p+q is 11 and it happens when p = 6 and q = 5.

Side note: p+q is smallest when we go with the largest perfect square factor.

6 0
1 year ago
The profit that a vendor makes per day by selling x elephant ears is given by the function P(x)= -0.004x^2+3.2x-200. Find the nu
dezoksy [38]

Answer:

The number of elephant ears that must be sold to maximize profit is 400.

Step-by-step explanation:

Given that,

The profit that a vendor makes per day is given by

P(x)= - 0.004x² +3.2 x -200

where x is number of elephant ears.

P(x)= - 0.004x² +3.2 x -200

Differentiating with respect to x

P'(x)= - 0.008x+3.2

Again differentiating with respect to x

P''(x) = -0.008

For maximum or minimum P'(x)=0

- 0.008x+3.2=0

⇒0.008x=3.2

\Rightarrow x=\frac{3.2}{0.008}

⇒ x = 400

P''(x)|_{x=400} = -0.008

Since at x=400, P''(x)<0, the profit is maximize.

P(400) = -0.004×400²+3.2×400-200

          =440

The number of elephant ears that must be sold to maximize profit is 400.

3 0
3 years ago
Explain why it does not matter what letter or symbol is used to find an unknown number
lawyer [7]
In an equation using x is just a place holder because those numbers are variables so it doesn't matter whether it is x or w.
6 0
3 years ago
The library is 14.2 km away from daniels apartment. The bus takes daniel 11.15 km of the way to the library. He has to walk the
SVETLANKA909090 [29]
He has to walk the remaining 3.05 kilometers.
5 0
3 years ago
Read 2 more answers
Other questions:
  • Find the zeros of y=x2-4x-9 by completing the square
    10·1 answer
  • Tom is on a diet. His diet plan allows him to have 1,000 calories for dinner. He’s chosen a menu of enchiladas (537 calories), a
    8·1 answer
  • Y/3x-z for x=3 y=4 and z=1
    12·1 answer
  • What is the sign of the product? Help plz
    14·1 answer
  • A total of 256 people visted an exhibit at a science museum in 8 hours. What was the unit rate of visitors per hour
    15·1 answer
  • You borrow money for 4 years. The total amount you repay is $7,840, which includes $840 in simple interest. How much was the pri
    12·2 answers
  • Peyton is going to invest $440 and leave it in an account for 5 years. Assuming the
    13·1 answer
  • There are 400 seats in a auditorium.the students are using 3/5 of the seats and the teachers are using 60 seats.How many seats a
    11·1 answer
  • What is the solution to -7+h=12?
    13·2 answers
  • ANSWER ASAP please &lt;3
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!