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upper and lower bounds PLEASE HELP ME

so i dont know what steps im missing but im only getting 3/5 marks so could someone please tell me the missing steps :
THE QUESTION
a rectangular floor tile is shown
its dimensions are given to the nearest 0.1 meters
width = 2.3m
length = 1.6m
the tile is only able to sustain a maximum pressure of 200 newtons per square meter (N/ m squared)
correct to the nearest 5 N/ m squared
given that pressure = force /area
work out the MAXIMUM force in newtons that can SAFELY be applied to the tile

MY WORKING OUT THAT HAS 3/5 MARKS
area
1.65 × 2.35 = 3.88
1.55 × 2.25 = 3.49
2.25 x 1.65 =3.71
1.55 x 2.35 = 3.64
pressure
upper bound = 202.5
lower bound = 197.5

SOMEONE PLEASE TELL ME WHAT IM MISSING

Reply 1

MarkFromWales

Your bounds are correct but you haven't worked out the force. Choose the appropriate bounds from those you have worked out and use the formula to work out the force (re-arrange the formula given so that force is the subject).

Reply 2

GCSE_beginner

Hi there
Just asking is this a Higher topic?
Because I want to do Higher maths for GCSE even though it may seem hard. I just don't feel that a 5 is good enough for me.