If there are only red, green and blue marbles in the bag, then given that 1/3 are blue, then red and green occupy 1-1/3=2/3 of the bag.
Use direct proportion:
2/3 bag : 5+7=12
1/3 bag : X
Cross multiply:
x=(1/3)*12รท(2/3)
=12/2
= 6 (blue marbles)
a bag of marbles contains 5 red,7 green ,and some blue.if 1/3 of the marbles in the bag are blue,how many blue marbles are in the bag?
2 answers
A rectangular block of aluminium 24 cm long and 12cm wide is melted and recast into cubes of edge 4 cm. 64m of aluminium is lost during the process. If 125 cubes are obtained calculate the height of the rectangular block before it was melted