On a school bus, there were $$\frac{7}{10}$$ as many boys as girls. After 6 boys alighted from the bus, there were $$\frac{2}{5}$$ as many boys as girls. <hr> How many children were there in the bus at first? ' <br> <input min="0" type="number" id ="imp6pg058q15_1" class="lineinput" placeholder="?" />