Let
x = number of minutes of local calls.
y = number of minutes of international calls.
By writing the system of equations we have:
0.06x + 0.15y = 69.84
x + y = 852
Solving the system
Clear y from equation two
y = 852-x
Replace y in equation 1
0.06x + 0.15 (852-x) = 69.84
Clear x
0.06x + 127.8 - 0.15x = 69.84
127.8 - 69.84 = 0.15x -0.06x
57.96 = 0.09x
x = 57.96 / 0.09 = 644
x = 644
Replace x in any of the two equations and clear y:
x + y = 852
y = 852-644
y = 208
answer
number of minutes of local calls = 644
number of minutes of international calls = 208
Answer:
30z^8
Step-by-step explanation:
5z^7.6z
= 5 x z^7 x 6 x z
= 5 x 6 x z^7 x z
= 30 x z^(7+1)
=30z^8
Answer:
(a) 1024 ways
(b) 243 ways
Step-by-step explanation:
When answers are independent, the total number of ways all questions can be answered is the product of the number of ways each question can be answered.
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<h3>(a)</h3>
The first question can have one answer 4 ways. The second question can be answered 4 ways for each of the ways the first question was answered. That is, the two questions can be answered 4×4 = 16 ways. Similarly, each additional question multiplies the number of ways the questions can be answered by 4.
The 5 questions can be answered 4×4×4×4×4 = 4^5 = 1024 ways.
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<h3>(b)</h3>
There are 3 ways to answer the first question incorrectly. Each additional question can be answered incorrectly 3 ways for each of the ways previous questions were answered. The total number of ways all questions can be answered incorrectly is ...
3^5 = 243
A student can answer all questions wrong in 243 different ways.
Answer:
Step-by-step explanation:
When "y varies directly with x" this means that:
where k is a number we need to find out (called the constant of proportionality if you care about that).
We can figure out what k is because they tell us when y= -252, x=84. Substituting those values into our equation we get:
and therefore:
.
So our equation or formula between y and x is:
.
So when x = 74, then:
Exact form:
17/12
Decimal Form:
1.416666666.....
Mixed number Form: 1 5/12
