(a) 32 orange marbles
the ratio of red : blue = 18 : 48 = 3 : 8 ( in simplest form )
the ratio of green : orange = 3 : 8 ( equal ratio )
divide green by 3 to obtain 1 part of ratio then multiply this value by 8 to obtain the amount of orange marbles
3 parts → 12
8 parts → 12 × 
= 32 orange marbles
Angle A should be equal to 47
5
11*---
8
----------
2
----
3
next
55
------
8
= ---------
2
------
3
next
3(55)
= ---------
16
next
165
= --------- or 10.3125
16
The equation looks like this:
26=x*3.5+8.50
where x is the number of pen you bought.
We solve it like this:
first, we subtract 8.50 from both sides:
17.50 =3.5*x
now we divide both sides by 3.5:
5=x
so you purchased 5 pens.
