There're 15 boys and 10 girls in miss li's class. she wants to group all the students so that each group has the same number of boys and girls as the other groups. what is the greatest number of groups she can have?

Which of the following transformations will always produce a congruent figure?

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?

What is the missing reason in the proof? segment addition congruent segments theorem transitive property of equality subtraction property of equality?