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
Mila [183]
4 years ago
13

10 pens cost £4.00 find the cost of 7 pens

Mathematics
2 answers:
Romashka-Z-Leto [24]4 years ago
5 0
The answer is £2.80. To find the cost of 1 pen, you divide £4 (all 10 pens) by 10 which gives you 40p. To find 7 pens, you multiply 40p (1 pen) by 7. £0.40 x 7 = £2.80
Nina [5.8K]4 years ago
3 0
Well, the first thing we need to do is divide 10 by 4. These teo numbers are the number of pens, and cost of them. So,
================================
10 / 4 = 2.5
--------------------------------------------------------
Now we have to use the answer we got, 2.5 which is the cost of 1 pen, and multiply it by 7.
================================
2.5 x 7 = 17.5
--------------------------------------------------------
This means that 7 pens cost <span>£</span>17.5






You might be interested in
An equation of the circle whose center is the origin and
tankabanditka [31]

Answer:

\fbox{\begin{minipage}{10em}Option C is correct\end{minipage}}

Explanation:

A circle whose center is (a, b) and radius r, has equation:

(x - a)^{2} + (y - b)^{2} = r^{2}

The center of circle is  given as origin (0, 0), therefore:

a = 0\\b = 0

This circle passes (3, 0), then the radius of circle is the distance (d) between origin (0, 0) and (3, 0)

d = \sqrt{(0 - 3)^{2} + (0 - 0)^{2} } = \sqrt{3^{2} } = 3

=> r = d = 3

Substitute a, b, and r back into original equation:

(x - 0)^{2} + (y - 0)^{2}  = 3^{2}

or

x^{2} + y^{2} = 9

Hope this helps!

:)

3 0
3 years ago
ANSWER ASAP PLEASE!!!!!!!!!!!! THANKS!!!!!!!!! :)
krok68 [10]

Answer: the answer is A

Step-by-step explanation:

6 0
3 years ago
Diego boils 10 cups of water. how many cups of oats should he add into the water
storchak [24]

Answer:

the answer is 5 cups. Hope this helps

6 0
3 years ago
Read 2 more answers
Name an equivalent ratio for 1/2 with a denominator of 20
Westkost [7]
To begin with, equivalent fractions represent the same part of a whole number. So I need to find a fraction, with a denominator of 20, that is the same value as 1/2: 
1/2 = ?/20
1*10/2*10 = 10/20

Since the denominator needed to be 20, I multiplied the numerator and the denominator (1/2) by 10 to get 10/20. So, 1/2 and 10/20 are equivalent.
8 0
3 years ago
Solve the system by using a matrix equation (Picture provided)
Katyanochek1 [597]

Answer:

Option b is correct (8,13).

Step-by-step explanation:

7x - 4y = 4

10x - 6y =2

it can be represented in matrix form as\left[\begin{array}{cc}7&-4\\10&-6\end{array}\right] \left[\begin{array}{c}x\\y\end{array}\right] = \left[\begin{array}{c}4\\2\end{array}\right]

A= \left[\begin{array}{cc}7&-4\\10&-6\end{array}\right]

X= \left[\begin{array}{c}x\\y\end{array}\right]

B= \left[\begin{array}{c}4\\2\end{array}\right]

i.e, AX=B

or X= A⁻¹ B

A⁻¹ = 1/|A| * Adj A

determinant of A = |A|= (7*-6) - (-4*10)

                                    = (-42)-(-40)

                                    = (-42) + 40 = -2

so, |A| = -2

Adj A=  \left[\begin{array}{cc}-6&4\\-10&7\end{array}\right]

A⁻¹ =  \left[\begin{array}{cc}-6&4\\-10&7\end{array}\right]/ -2

A⁻¹ =  \left[\begin{array}{cc}3&-2\\5&-7/2\end{array}\right]

X= A⁻¹ B

X=  \left[\begin{array}{cc}3&-2\\5&-7/2\end{array}\right] *\left[\begin{array}{c}4\\2\end{array}\right]

X= \left[\begin{array}{c}(3*4) + (-2*2)\\(5*4) + (-7/2*2)\end{array}\right]

X= \left[\begin{array}{c}12-4\\20-7\end{array}\right]

X= \left[\begin{array}{c}8\\13\end{array}\right]

x= 8, y= 13

solution set= (8,13).

Option b is correct.

3 0
3 years ago
Other questions:
  • \frac{1}{5}k-9=\frac{3}{5}k-7
    15·1 answer
  • Please graph y = (x+4)/2
    9·1 answer
  • An agent makes 16% commission on an athlete's signing bonus. If the bonus is $26,000
    6·1 answer
  • What is an example of a mathematical equation?
    7·1 answer
  • A company stock is selling at $30 a share a month later was selling at $33 a share what is the percent increase
    7·2 answers
  • The data set shows the number of hours per week that each student in a class spends studying at home. What is the shape of the d
    15·1 answer
  • Find x make sure you simplify your answer
    15·1 answer
  • ‼️Someone help please.. <br> Find the missing term in each sequence
    9·1 answer
  • Write your answer as a whole number and remainder.<br> 31+4=R
    9·1 answer
  • What is the solution of this quadratic equation? x2 + 10 = 0
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!