Kerry's piggy bank contains only quarters and dimes. There are 88 coins and a total of $16.30. Which system of equations will determine the number of quarters and the number of dimes in Kerry's piggy bank?
I really don't understand so if someone would please explain this to me that would be much appreciated! Thank you again so much!
Help with math problem...?
2015-12-02 7:02 am
回答 (2)
2015-12-02 7:24 am
d: number of dime → 1 dime = 10 cents = 0.1 $
q: number of quarter → 1 quarter = 25 cents = 0.25 $
You have 88 coins: → d + q = 88 → d = 88 - q ← equation (1)
…and a total of $16.30: → 0.1d + 0.25q = 16.3 ← equation (2)
You start with the equation (2)
0.1d + 0.25q = 16.3 → recall (1): d = 88 - q
0.1.(88 - q) + 0.25q = 16.3
8.8 - 0.1q + 0.25q = 16.3
0.15q = 16.3 - 8.8
0.15q = 7.5
q = 7.5/0.15
→ q = 50
Recall (1): d = 88 - q
d = 88 - 50
→ d = 38
q: number of quarter → 1 quarter = 25 cents = 0.25 $
You have 88 coins: → d + q = 88 → d = 88 - q ← equation (1)
…and a total of $16.30: → 0.1d + 0.25q = 16.3 ← equation (2)
You start with the equation (2)
0.1d + 0.25q = 16.3 → recall (1): d = 88 - q
0.1.(88 - q) + 0.25q = 16.3
8.8 - 0.1q + 0.25q = 16.3
0.15q = 16.3 - 8.8
0.15q = 7.5
q = 7.5/0.15
→ q = 50
Recall (1): d = 88 - q
d = 88 - 50
→ d = 38
2015-12-02 7:18 am
I believe the answer is system of linear equations with two variables.
Like a1x+b1y=c1.
Like a1x+b1y=c1.
收錄日期: 2021-04-21 15:31:50
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