30b + 100u = 900
5b + 25u = 200....multiply by -6
------------------
30b + 100u = 900
-30b - 150u = - 1200 (result of multiplying by -6)
------------------add
-50u = - 300
u = 6 <== upgrated phones sold
30b + 100u = 900
30b + 100(6) = 900
30b + 600 = 900
30b = 900 - 600
30b = 300
b = 10 <== basic phones sold
50 Dollars For The Member-Ship
2 Dollars For The Class (C)
Y=Total (unknown because you dont know how may classes)
Y=50(C)
Answer: The price of item is $495.
Step-by-step explanation:
Since we have given that
Amount that Sara have = $90
Amount that Rachel have = $405
If they combine their money they will have enough to buy item.
So, Price of item would be
Amount that Sara have + Amount that Rachel have

Hence, the price of item is $495.