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IPS practice tests. Surface area. Am I missing something

Posted: Thu Sep 03, 2009 10:34 am
by yoyo123
:oops:

once again I am stumped

Does anyone have the IPS 10 practice papers?

test 3 has a question on surface area. There is a net which folds to make a box. Each square square has sides of 2cm. The net has 4 rectangles 4x 2 squares (so 4cm x 8cm), which are the sides of teh box and 2 squares , the ends) which are 2 squares by 2 squares (so 4cm x4 cm)

It asks for the surface area of the box.

Choices given are

160 cubic centimetres
60 cubic centimetres
120 cubic centimetres
48 cubic centimetres
80 cubic centimetres


answer given is 80 square centimetres.

I worked out area of all the sides and added them, thinkig this would be surface area. no answer matched

then thought it may be volume and a misprint ( given cubic centimetres) still no match.


It is probably right under my nose but I am obsessed now!!

all help gratefully received.

Posted: Thu Sep 03, 2009 11:22 am
by yoyo123
I have it in good authority that the answer is 160 sq centimetres, so a case of bad proof reading.

My faith in my abilities has been restored!!

Posted: Thu Sep 03, 2009 12:17 pm
by bucks mum1
I would agree with 160 sq centimetres.

4 rectanges at 4 x 8 cm
32cm x 4 = 128 sq centimetres

2 squares at 4 x 4 cm
16cm x 2 = 32 sq centimetres

128 + 32 = 160 sq centimetres.

Posted: Thu Sep 03, 2009 12:29 pm
by Milla
yes, 160, most def. (feeling a little bit excited that I got it! :cry: )
and NOT cubic! :wink: