Lizzie has 30 coins that total $4.80. All of her coins are dimes, D, and quarters, Q. Algebraically determine how many of each t
1 answer:
Lizzie has 18 dimes and 12 quarters
<em><u>Solution:</u></em>
Let "d" be the number of dimes
Let "q" be the number of quarters
We know that,
value of 1 dime = $ 0.10
value of 1 quarter = $ 0.25
Given that LIzzie has 30 coins
number of dimes + number of quarters = 30
d + q = 30 ---- eqn 1
Also given that the coins total $ 4.80
number of dimes x value of 1 dime + number of quarters x value of 1 quarter = 4.80
0.1d + 0.25q = 4.8 ------ eqn 2
Let us solve eqn 1 and eqn 2
From eqn 1,
d = 30 - q ---- eqn 3
Substitute eqn 3 in eqn 2
0.1(30 - q) + 0.25q = 4.8
3 - 0.1q + 0.25q = 4.8
0.15q = 1.8
<h3>q = 12</h3>From eqn 3,
d = 30 - 12
<h3>d = 18</h3>Thus she has 18 dimes and 12 quarters
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Given that Angelo spends the same amount everyday from the amount in
the lunch card, the function of the amount remaining is a linear function.
- The constant rate of change of the function is; <u>-5.25</u>
- The two ordered pair used to find the constant rate of change are; <u>(1, 44.75) and (2, 39.5)</u>
Reasons:
The amount Angelo's mother put on the lunch card = $50
A possible table of values to the question is presented as follows;
Required:
The constant rate of the function that gives the amount remaining from the
amount Angelo's mother put on his lunch card.
Solution:
The two ordered pair that can be used to find the slope or constant rate of change are;
(x₁, y₁) = (1, 44.75), and (x₂, y₂) = (2, 39.5)
With the above two ordered pairs, we have the constant rate of change of the function given as follows;
The constant rate of change for the function that gives the amount remaining in the lunch card is; <u>-5.25</u>
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