Answer:
114
Step-by-step explanation:
so lets call shelf 1 x
shelf 2 is twice size + 18 of shelf 1 so it is 2(x)+18
shelf 3 is 12 less than shelf 1 so x-12
shelf 4 is four more so x+4
Add them all together and it should be 5x+10= 2.5 m or 250 cm
Solve for x using cm
then plug into shelf 2 equation
