The rate is 12! why Well easy if you divide 72 by 6 is 12
There's an infinite amount of numbers that round to 8.21 when rounded to the nearest hundredth, for example:
8.211
8.209
8.214
8.21145683204
etc...
Just pick whichever two numbers you like :)
Answer:
Let fertilizer be F
and peat moss be P
since F is proportional to P
F = kP
where, k = constant of proportionality
k = F/P
putting in the values,
k = (3/4) /12
k = 3/4 * 1/12
k = 1/16
Therefore the constant of proportionality is 1/16.