Answer:
i) pi×4500 cm³
ii) pi×600 cm²
iii) 14 liters
Step-by-step explanation:
in general : the diameter is 30 cm, the radius is half of that (15 cm)
i)
the volume of a cylinder is base area times height.
Vc = pi×r²×h = pi×15²×20 = pi×225×20 = pi×4500 cm³
ii)
similar to volume, the side "mantle" area of the cylinder is the circumference of the base area times height.
surface area of the cylinder mantle is
Scm = 2×pi×r×h = 2×pi×15×20 = pi×30×20 = pi×600 cm²
iii)
for this we need now to do the multiplication with pi and then convert the cm³ to liters.
1 liter = a cube of 10 cm side length = 10×10×10 = 1000 cm³
pi×4500 = 14137.17 cm³ = 14.13717 liters or rounded 14 liters
Answer:
6.11km/hr
Step-by-step explanation:
Let the speed that Kelli swims be represented by Y
Speed of the river = 5km/hr
Distance = Speed × Time
Kelli swam upstream for some distance in one hour
Swimming upstream takes a negative sign, hence:
1 hour ×( Y - 5) = Distance
Distance = Y - 5
She then swam downstream the same river for the same distance in only 6 minutes
Downstream takes a positive sign
Converting 6 minutes to hour =
60 minutes = 1 hour
6 minutes =
Cross Multiply
6/60 = 1/10 hour
Hence, Distance =
1/10 × (Y + 5)
= Y/10 + 1/2
Equating both equations we have:
Y - 5 = Y/10 + 1/2
Collect like terms
Y - Y/10 = 5 + 1/2
9Y/10 = 5 1/2
9Y/ 10 = 11/2
Cross Multiply
9Y × 2 = 10 × 11
18Y = 110
Y = 110/18
Y = 6.1111111111 km/hr
Therefore, Kelli's can swim as fast as 6.11km/hr still in the water.
Answer:
greater than
Step-by-step explanation:
7/8 is greater than 4/8
Answer: Hope This Helps!
Step-by-step explanation:
Simplify the expression.
Exact Form:
87/40
Decimal Form:
2.175
Mixed Number Form:
2 7/40
Multiplying 20 by 320% is the same thing as multiplying 20 by 3.2, or 20(3.2)=64. Hope this helped!
