The problem states that 30 students applied, and 40% of them are boys. The rest are girls. We need to find out how many girls will be without an escort and calculate everything else.

1. Problem Description

The problem states that 30 students applied, and 40% of them are boys. The rest are girls. We need to find out how many girls will be without an escort and calculate everything else.

2. Solution Steps

First, calculate the number of boys:

$Number\,of\,boys = Total\,students \times Percentage\,of\,boys$

$Number\,of\,boys = 30 \times 40\% = 30 \times \frac{40}{100} = 30 \times 0.4 = 12$

Next, calculate the number of girls:

$Number\,of\,girls = Total\,students - Number\,of\,boys$

$Number\,of\,girls = 30 - 12 = 18$

The problem asks "How many girls will be without an escort?". The problem does not provide any information related to that so we assume we need to provide the total number of girls. The problem also requires to "calculate everything else", we understand that we need to determine the number of boys, the number of girls, the total number of students. However, since the total number of students is given (30) and the number of boys and girls have been calculated, there is nothing left to calculate.

3. Final Answer

Number of boys: 12

Number of girls: 18

Number of girls without escort: Information not available in the problem. We'll assume the question is actually: total number of girls. So,

1

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