Question

Please help me! I've tried so hard and just cant

Answer 1

So... 4 folks, working for 8hours per day, do it in 15days

hmm alrite...so 4 folks working for 8hrs in 1 day, each one does 8, 4 of them, 4*8 = 32, so, they do 32 workhours every day, now for 15 days, that'd be 32*15, or 480

so, the whole job really takes 480 hours

now hmm let's see, the firm decides to increase the folks, but decrease the hours, so, 5 folks each working 6hours every day

how many workhours total? well 5*6 = 30
each is working 6hrs, 5 of them, so 30 workhours

how long will it take them if they only do 30 workhours everyday?

well the whole job is 480hours

$\bf \cfrac{30hrs}{day}=480hrs\implies \cfrac{30hrs}{480hrs}=day\implies \cfrac{1}{16}=day \\\\\\ \textit{so, if they do }\frac{1}{16}\textit{ daily, to complete, they'd need }\frac{16}{16}\\ \\\\\ \textit{for the whole, thus }16 days$