Given that the total student population of the school is 560 and the number of girls is 1427% of the number of boys.
Let the total number of boys in the school be B.
Hence, number of girls =1427%×B=1007%×B
⇒17×B=B7
Also, total number of boys + total number of girls = Total students
∴ B+B7=560⇒8B7=560
∴ B=560×78=490
So, number of girls =560−490=70
Hence, there are 70 girls in the school.