a field of grass feeds 28 cows for 6 days .how many days would the same field feed 21 cows?
Answers
Answer:
90
Step-by-step explanation:
If 45 cows an graze a field in 13 days, how many cows will graze the same field in 9 days?
If 45 cows an graze a field in 13 days, how many cows will graze the same field in 9 days?So, the “speed” of one cow is “1/45 th part of the field in 13 days”. Or, more universally “(1/45)/13 part of the field in one day”. That is 1/585.
If 45 cows an graze a field in 13 days, how many cows will graze the same field in 9 days?So, the “speed” of one cow is “1/45 th part of the field in 13 days”. Or, more universally “(1/45)/13 part of the field in one day”. That is 1/585.Si, if we have 9 days for the same field, how many cow do we need? We divide the number of “the fields” by “the speed of one cow” and have the quantity of cows for “one-day job”. That’s “1 field divided by (1/585) fields-by-cow-per-day”. That is “585 cows” (for one day).
If 45 cows an graze a field in 13 days, how many cows will graze the same field in 9 days?So, the “speed” of one cow is “1/45 th part of the field in 13 days”. Or, more universally “(1/45)/13 part of the field in one day”. That is 1/585.Si, if we have 9 days for the same field, how many cow do we need? We divide the number of “the fields” by “the speed of one cow” and have the quantity of cows for “one-day job”. That’s “1 field divided by (1/585) fields-by-cow-per-day”. That is “585 cows” (for one day).But we’re not in a hurry, we have 9 days and can go 9 times slower. We’ll need 9 times less of the cows quantity. So, that’s “585/9” and that’s 65 cows for 1 field and 9 days.