Answer:
Darlene bought more fabric
Darlene bought 3.4 yards more
Step-by-step explanation:
Darlene = 7 yards + 20% extra
= 7 yards + (20% of 7 yards)
= 7 + (20% × 7)
= 7 + (0.2 × 7)
= 7 + 1.4
= 8.4 yards
Chris = 4 yards + 25% of 4 yards
= 4 yards + (25% of 4 yards)
= 4 + (25% × 4)
= 4 + (0.25 × 4)
= 4 + 1
= 5 yards
Darlene bought more fabric
How much more?
Darlene - Chris
= 8.4 yards - 5 yards
= 3.4 yards
Darlene bought 3.4 yards more
C(x) = 400 + 20x - 0.2x²
c(30) = 400 + 20(30) - 0.2(30)²
= 400 + 600 - 0.2(900)
= 1000 - 180
= 820
It costs $820 when 30 radios are produced.
Marginal cost is how much it would cost to make one MORE of the same product so now we find how much it costs to produce 31 radios and compare the two.
c(31) = 400 + 20(31) - 0.2(31)²
= 400 + 620 - 0.2(961)
= 1020 - 192.2
= 827.8 or ≈828.
Now we find the difference which means we subtract the two.
828 - 820 = 8.
Your marginal cost is $8.
To compare we can also do 29 radios.
c(29) = 400 + 20(29) - 0.2(29)² = 811.8 or ≈812
820 - 812 = 8.
to put them together and add them.
Basically there are 3 addition properties and they are associative property, identity property, and commutative property.
Commutative property is just changing the order of the addends. Example: 26+19+34+21= 21+34+19+26
Identity Property is just adding a 0 to the number that doesnt change anything. Example: 26+19+34+21 +0 = 100
Associative property is just changing the grouping of the addends. Example: (26+19) + (34+21)
I know these properties may be complicated i know inhate them too haha but i hope i helped :) if you want you can search up the distributive property too but its with multiplication and addition combined and its harder but i think these are the 3 main properties.
