Answer:
what's is the he question
Step-by-step explanation:
?
The answer is 180 minutes. because you multiply 30 times 0.20 and you get 6. Then you multiply 6 times 30 and get 180 minutes. And 180 minutes in hours is 3 hours.
The numbers of new CDs is 30 and the old CDs is 21.
To solve this problem, we have to write a system of equations in which we would know the numbers of each types of CD she bought.
<h3>System of Equations</h3>
This is used to solve a series or complex of word problems in which we can represent in a mathematical statements;
- Let n represents numbers of new CDs
- Let u represents numbers of old CDs
The equations can be represented as

Let's take equation (i)
Making n the subject of formula

we can put equation (iii) into equation (ii)

Let's put the value of u into equation (i)

From the calculations above, the numbers of new CDs is 30 and the old CDs is 21.
Learn more on system of equations here;
brainly.com/question/13729904
Answer: x
=
−
30 7
Decimal Form :
x
=
−
4.
¯¯¯¯¯¯¯¯¯¯¯¯
285714
Mixed Number Form :
x
=
−
4
2
7
Step-by-step explanation:
Answer:
Step-by-step explanation:
Lets Price of a DVD is fixed i.e. 15
and One CD price is 5 (Not fixed)
In First situation
2 DVDs and 1 CD cost = 35 as given
2 x 15 + 5 = 35
Lets one CD price is 7.5
In Second situation
2 x 15 + 2 x 7.5 = 45
Its mean CD price may be between 5 to 7.5
In asked scenario, Martin has 50
1 DVD and 3 CDs?
1 x 15 + 3 x 7.5 = 37.5
37.5 is lesser than 50
Hence Martin has enough to buy 1 DVD and 3 CDs.