Answer:
2,802 boys and 3,693 girls went to Disneyland this weekend
Explanation:
System of Equations
Let's call:
b = Number of boys who went to Disneyland this weekend.
g = Number of girls who went to Disneyland this weekend.
The first condition states there was a total of 6,405 people who went to Disneyland this weekend, thus:
![b+g=6,405\qquad\qquad [1]](https://img.qammunity.org/2021/formulas/mathematics/college/3341bd4uzh9szudvvsll7v16tlg83xfyh9.png)
The second condition states that the ratio of boys to girls is 7 to 9. This can be written as:
![\displaystyle (b)/(g)=(7)/(9)\qquad\qquad [2]](https://img.qammunity.org/2021/formulas/mathematics/college/8b0wb4t2bheq9oaht1jo51qaievf2ul4oz.png)
To eliminate denominators, multiply [2] by 9g:

Simplify:
![9b=7g\qquad\qquad [3]](https://img.qammunity.org/2021/formulas/mathematics/college/zftxjhpjvu4vxacwht9h921wl6kvgtfbrn.png)
From [1]:

Substituting into [3]

Operating:

Simplify:

Solve:

Take the approximate value:
g=3,603
Find b:

2,802 boys and 3,693 girls went to Disneyland this weekend
Note: Due to the nature of the problem, the results had to be rounded to the nearest integer. This condition makes the ratio not being exactly as required.