The first problem, decomposition prime factor, 455=5x7x 13. This question is easy to answer. Put out five first, and then you can find the ones behind one by one. The second question is that the part of the ribbon excluding the bow is 30x4= 120cm (draw a picture yourself, the ribbon will circle the box, and you will understand it at a glance), and the bow is 65438+. 2-(3/4+5/8)=5/8 decimeter Question 4, the second shipment is 2.7+2/5=3. 1 ton, and the shipment of a certain * * * is 3. 1+2.7=5.8 ton Question 5, purely from the physical point of view, the second shipment is.

The second basket weighs 1/4-2/ 17=9/68.