Answer:
520 boys (along with 400 girls)
Explanation:
Let B be the number of boys and G be the number of girls
We know that the ratio of boys to girls is 13:10, so this can be represented as B/G=13/10
We know that there are 120 more boys than girls, so the number of boys can be represented as B=120+G.
Since the second equation is already solved for B, the number of boys, we can substitute this value in the first equation and solve for G, the number of girls:
B/G=13/10
(120+G)/G=13/10
10(120+G)=13G
1200+10G=13G
1200=3G
400=G
Now that we know there are 400 girls in the camp, we can substitute this value into the second equation and get B, the number of boys:
B=120+G
B=120+400
B=520
Therefore, there were 520 boys at the camp.