Answer:
C = commutative property of Addition
for question 1
Area of Base B =45×25 = 1125 cm²
perimeter of base P = 2(45+25) = 140 cm
Height = 15 cm
Using the formula
Surface area = 2B + Ph
A = 2×1125 + 140×15= 4350 cm²
Voume = Bh = 1125×15= 16875 cm³
For question 2,
Area of base = 7× 5/2= 17.5 cm²
Perimeter of base = (7+7+7) = 21 cm
Surface area = 2B + Ph
Surface area of prism = 2×17.5+ 21×10 = 245cm²
Volume = Bh = 17.5×10 = 175 cm³
Answer: c
Step-by-step explanation: I took the test
A collection of nickels and dimes is worth $4.40. There are 53 coins in all. How many nickels are there?
Nickel is a US coin worth 5 cents or 0.05.
Dime is a US coin worth 10 cents or 0.10
n + d = 53
0.05n + 0.10d = 4.40
n = 53 - d
0.05(53 - d) + 0.10d = 4.40
2.65 - 0.05d + 0.10d = 4.40
0.05d = 4.40 - 2.65
0.05d = 1.75
d = 1.75 / 0.05
d = 35
n = 53 - d
n = 53 - 35
n = 18
There are 18 nickels and 35 dimes.
0.05n + 0.10d = 4.40
0.05(18) + 0.10(35) = 4.40
0.90 + 3.5 = 4.40
4.40 = 4.40
Answer:
total pages = 20
Step-by-step explanation:
60% of an unknown number is 12
Let the unknown number (total pages) be x.
60/100 of x = 12
60/100 * x = 12
3/5 x = 12
x = 12 * 5/3
x = 20