2. Formulate the following problems as a pair of equations, and hence find their solutions: (1) Ritu can row downstream 20 km in 2 hours, and upstream 4 km in 2 hours. Find her speed of rowing in still water and the speed of the current.
Answers
Answer:
Let Ritu’s speed of rowing in still water and the speed of the stream be x km/h and y km/h respectively.
Ritu’s speed of rowing;
Upstream = ( x - y ) km/h
Downstream = ( x + y ) km/h
According to the question:
Ritu can row downstream 20 km in 2 hours,
2( x + y) = 20 [Since, Distance = Speed × Time]
x + y = 10 ....(1)
Ritu can row upstream 4 km in 2 hours,
2( x - y) = 4
x - y = 2 ....(2)
Adding equation (1) and (2), we obtain
x + y + x - y = 10 + 2
2x = 12
x = 6
Putting x = 6 in equation (1), we obtain
6 + y = 10
y = 4
Hence, Ritu’s speed of rowing in still water is 6 km/h and the speed of the stream is 4 km/h.
Answer:
The ratio in the property of a family members are so under the ratio of property of father and mother is 5:2 mother and daughter is 3:4 and daughter and son is6:7 find the continued the actual in property