100 nut in = 1 minute.....1000 nut in = 10 minute ......
then 5 min rest.......
So....in 10 + 5 = 15 minute = 1000 nut......then....in 30 minute = 2000 nut
75 bolt in = 1 minute..... 1500 bolt in = 20 minute......
then 10 minute rest.......
So.....in 20 + 10 = 30 minute = 1500 bolt......
So ... in every 30 minute ... nut made = 2000 ... bolt made = 1500 ... so ... nut bolt pair made = 1500 ...
So......1500 nut bolt pair made in = 30 minute.....
So....7500 nut bolt pair made in = [ 7500 / 1500 ] × 30 = 150 minute...
Now....why didn't we figure out time needed to make 9000 pair at once...why did we stop at 7500....?
Its cuz....in 150 minutes.... Already 10000 nuts made....and bolt made 7500.....dats why pair made 7500.....
Now...just when new 1500 bolt is made...9000 pair will be made.... so only 20 minute is needed to make new
1500 bolt...cuz da 10 minute after is da rest time...we wont include dat....
So...after 20 more minutes.... total time passed = 150 + 20 = 170 minute .....
...... and total pair made = 7500 + 1500 = 9000.....
so...only 170 min .....
! nah id win!