ANSWER
The number of boys in the ward are 13
Step-by-step explanation
Given that;
The total number of children in the ward is 52
Since 75% of the children are girls, then we can find the number of girls below

Recall,
Number of children = number of boys + number of girls
we can calculate the number of boys using the relationship above
52 = number of boys + 39
Subtract 39 from both sides
52 - 39 = number of boys + 39 - 39
13 = number of boys
Number of boys in the ward is 13
Hence, the number of boys in the ward are 13