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A piece of cardboard 1.2 meters long and 70 cm wide is cut into a round teaching aid with a diameter of 30 cm. How many pieces can be cut at most?
1.2m = 120cm
120÷30=4
70÷30=2………… 10 cm
Up to 4 × 2 = 8 pieces
The teacher used a piece of rope to make teaching aids. 70% of the rope was used for the first time and 7 / 10 for the second time. It was just used up. The rope was () meters long
The length of this rope is 7 / 10 (1-70%) = 7 / 3 (m)
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