A class is divided into 2 batches for a school picnic. One batch has boys and girls in the ratio 3 : 4 and the other batch has it in the ratio 2 : 3. There are 20 more students in the first batch than the second. Find the total number of girls in the first batch if the number of boys in the second batch are 20.
The ratio of the 2nd batch = 2 : 3
Let the number of boys be 2x and number of girls be 3x
Total number of students in the 2nd batch = 2x+3x=5x=5×10=50
⇒ Number of students in 1st batch =50+20=70
Let the number of boys in 1st batch = 3x and number of girls = 4x
According to the question,
∴ Number of girls in 1st batch = 4x=4×10=40