1
2.(78.5%) (1.57) times
3、
(1(25+30) × 20 ÷ 2 = 550 (m) 550 ÷ 0.4 =1375 (tree).
(2) 1.30m = 130(DM)+030≈30≈4≈90≈3 = 3。
﹙3﹚60×35=2 100﹙㎝﹚2 100÷50=42﹙㎝﹚﹙42+64﹚×2=204﹙㎝﹚=2.04﹙m﹚
﹙4﹚3×4÷5=2.4﹙㎝﹚ 24×9÷2= 10.8﹙㎝﹚
Page 56
1、C A B B
2, the first above, the second front, the third side.
3、﹙ 1﹚ 20dm?
(2) 1 3 1
4. Draw two circles with a radius of 1 cm.
Is the surface area 18.84㎝? Volume 6.28㎝?
Page 57
1、﹙ 1﹚ 120L
﹙2﹚324㎝? 2 16㎝?
﹙3﹚ 72㎝? 48㎝?
2. The volume is 20× 16× 7 = 2240 ㎝? (Height: 2240 ~16×10 ~ =14 ~)
3. The volume is 28.26× 2×1/3 =18.84m? The bottom area is 3. 14×2? = 12.56﹙m? (Height18.84 ÷12.56 =1.5 〃 m)
4、8dm = 80㎝4dm = 40㎝80×40×5= 16000﹙㎝? ﹚ 16000÷4=4000﹙㎝? ﹚
Handmade, hope to adopt, thank you.