Answer:
1100 boys were in the parade
Explanation:
1650 students took part in a parade, there were twice as many boys as girls
B = number of boys
G = number of girls
B + G = 1650
We know that there were twice as many boys as girls, so
B = 2G
G = (1/2)b (substitute this into B+G = 1650)
B + 1/2B = 1650
After solving, we know that there were 1100 boys