SOLUTION: a field is 90 m by 70 m.A man walks round in at the rate of 4 km. per hour. What time will he take in making 5 rounds?

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Question 1024531: a field is 90 m by 70 m.A man walks round in at the rate of 4 km. per hour. What time will he take in making 5 rounds?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The perimeter is:
+P+=+2%2A90+%2B+2%2A70+
+P+=+180+%2B+140+
+P+=+320+ m
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His speed is:
+4000+ m/hr
----------------
5 rounds is:
+5%2A320+=+1600+ m
--------------------
+d+=+r%2At+
+t+=+d%2Fr+
+t+=+1600+%2F+4000+
+t+=+.4+ hrs
Convert to minutes:
+.4%2A60+=+24+
He takes 24 min to make 5 rounds