The gardeners is digging holes around a circular garden that has a circumference of $$300\rm{m}$$ as they want to plant trees around the garden. At first, they dig the holes at every $$3\rm{m}$$. But when they finish digging the $$30^{th}$$ holes, they receive a new order from their supervisor which the need to plant the trees with a constant interval of $$5\rm{m}$$. How many more holes they need to dig to complete the job? 
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