Alexey wrote '1*2*3*... 9 = 21' on the board, inserting a plus or minus signs in place of each little star. Sasha changed some of these signs to their opposites so that the result he got was 20. Prove that one of the boys made a mistake.​

The table below lists recommended amounts of food to order for 10 party guests. how much of each food item should nathan and amanda order for a graduation party with 55 guests? use the table to answer. item amount fried chicken 16 pieces lasagna 7 pounds deli meats 1.8 pounds sliced cheese 1 and two fifths pounds bakery buns 1 dozen potato salad 2 pounds