X = pennies
3x = nickels
x-2 = dimes
0.01x + 0.05(3x) + 0.10(x-2) = 1.10
0.01x + 0.15x + 0.10x - 0.20 = 1.10
0.26x-0.20 = 1.10
0.26x = 1.30
x = 1.30 / 0.26 = 5
5 pennies
5-2 = 3 dimes
3*5 = 15 nickels
check: 5 pennies = 0.05, 3 dimes = 0.30, 15 nickels = 0.75
0.75 + 0.30 + 0.05 = 1.10
pennies = 5
nickels = 15
dimes = 3
He included another variable - time. He should have given both brands the same amount of time to work. The only variable should have been the brands. Parker has introduced another variable and therefore his results are invalid.
Answer: it's the third one and the first one
Step-by-step explanation:
Answer:
$63.60
Step-by-step explanation:
After the 25% markup, the price is ...
$60 + 0.25·60 = $75
After the 20% discount, the price (before tax) is ...
$75 - 0.20·75 = $60
After tax is added, the price is ...
$60 + 0.06·60 = $63.60
_____
Effectively, the original price is multiplied by ...
(1.25)·(0.80)·(1.06) = 1.06
The resulting price with tax is ...
1.06·$60 = $63.60