hello, if someone can give me a hand with this upper and lower bound excercise please? l get 3 marks of 5 but l cant find what l am missing please thanks

  maximum "safe"  Force = 415.58 N

Step-by-step explanation:

Length = 1.2 m

lower bound is 1.15 (because it rounds up to 1.2)

upper bound is 1.24 (because it rounds down to 1.2)

Note: 1.25 would round up to 1.3

width = 2.5 m

lower bound is 2.45 (because it rounds up to 2.5)

upper bound is 2.54 (because it rounds down to 2.5)

Note: 2.55 would round up to 2.6

Pressure = 150 N/m²

lower bound is 147.5 (because it rounds up to 150)

upper bound is 152.4 (because it rounds down to 150)

Note: 152.5 would round up to 155

Max "safe" Force means minimum Area and minimum Pressure (lower bounds)

Force = Area x Pressure

           = length x width x Pressure

           = 1.15 x 2.45 x 147.5

           = 415.58

4/6 = 2/3

so it should take 3/3 hours per man. so 9 hours is the answer 3*3 =9

step-by-step explanation: