Answer:
3/4 or .75
Step-by-step explanation:
math
Answer:
rate boat = 15 mph
rate current = 5 mph
explanation:
d = r * t
t = d/r
240 / (r_boat + current) = 12 Multiply both sides by r_boat + r_current.
240 = 12(r_boat + current)
240/ (r_boat - current) = 24 Multiply both sides by r_boat - r_current
240 = 24*(r_boat - current)
Since the distances are the same in both equations, you can equate the right side of each.
12 (r_boat + current) = 24(r_boat - current) Divide by 12
r_boat + current = 2 (r_boat - current) Remove the brackets.
r_boat + current = 2*r_boat - 2* current add 2 currents to both sides
r_boat + 3currents = 2*r_boat Subtract r_boat both sides
3 currents = r_boat.
240 = 12*(r_boat + current. Divide by 12
20 = r_boat + current Put 3 currents in for r_boat
20 = 3currents + 1 current Combine
20 = 4 currents Divide by 4
5 = current
The rate of the current = 5 miles / hour
3 currents = r_boat
3*5 = rate_boat
15 = rate of the boat
Answer:
a=20 m²
b=21 cm²
c=36 dm²
Step-by-step explanation:
A) 12²+16²=a²
144+256=a²
400=a²
√400=a
a=20
B) 28²+b²=35²
784+b²=1225
b²=1225-784
b²=441
b=√441
b=21
C) c²+15²=39²
c²+225=1521
c²=1296
c=√1296
c=36
Answer:
"The mean is the average of the numbers: a calculated "central" value of a set of numbers. To calculate it: add up all the numbers, then divide by how many numbers there are." -- Math is Fun