苏教版五年级上册总复习课件-简便运算
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课件13张PPT。期末总复习执教：周家根五年级上册数学1、直接写出得数。 (1)0.5×0.2= (2)50×0.2= (3) 500×0.2=(4)2.4×4= (5)2.5×0.4= (6)0.25×40=(7)0.125×8= (8)12.5×8= (9)1.25×80=2、在括号里填上适当的数。(1)0.32=4×( ) (2)1.02=1+( ) (3)0.99 =1- ( ) (4)9.8=( )-( ) 0.1101009.61101100 1000.080.020.01100.2用字母表示运算定律加法交换律是
加法结合律是
乘法交换律是
乘法结合律是
乘法分配律是a+b=b+a(a+b)+c=a+(b+c)a×b=b×a(a×b) ×c=a×(b×c)(a+b) ×c=a×c+b×c
简便运算的复习先说说怎样算简便，再简便计算。 3.68＋0.6＋0.4 33.8＋6.2＋12.443.5＋12.72＋6.5＋2.28 53.6＋14.7＋5.3= 3.68＋(0.6＋0.4)
= 3.68＋1
=4.68= 40 + 12.4
= 52.4= (43.5 + 6.5) + (12.72 + 2.28)
= 50 + 15
= 65= 53.6 + (14.7 + 5.3)
= 53.6 + 20
= 73.6你能简便计算下面各题吗？16.45 – 3.7 – 6.3 4.02 – 1.8 + 1.985.9 + 0.1 - 5.9 + 0.1 13.64 - 2.8 - 3.64= 16.45 – (3.7 + 6.3)
= 16.45 –10
= 6.45= (4.02 + 1.98 )– 1.8
= 6 – 1.8
= 4.2=( 5.9 - 5.9 )+( 0.1 + 0.1 )
=0 + 0.2
= 0.2= 13.64 - 3.64 - 2.8
= 10 - 2.8
= 7.26.43 – (1.4 – 0.57） 9.36 – (4.36 – 3.5)= 6.43 – 1.4 + 0.57
= 6.43 + 0.57 – 1.4
= 7 – 1.4
= 5.6= 9.36 – 4.36 + 3.5
= 5 + 3.5
= 8.5先说说怎样算简便，再简便计算。7.4×8.3 + 1.7×7.4 0.125×0.25×8×4 9.43×99 + 9.43 25×3.2×1.25= 7.4×8.3 + 1.7×7.4
= 7.4×(8.3 + 1.7)
= 7.4×10
=74=(0.125×8)×(0.25×4)
=1×1
=1= 9.43×(99 + 1)
= 9.43×100
=943= (25×0.4 )×(8 ×1.25)
=10×10
=100你能简便计算下面各题吗？47500÷2.5÷4 26.4 ÷（6×0.4）= 47500÷（2.5×4）
= 47500×10
=4750= 26.4 ÷6 ÷ 0.4
=4.4 ÷ 0.4
=116.1×0.99= 6.1×(1 – 0.01)
= 6.1×1 – 6.1×0.01
= 6.1 – 0.061
= 6.039 85×8÷85×8 7.8×2.1+78×0.79 6.3÷1.4= 85÷85×8×8
=1×8×8
=64= 7.8×2.1+7.8×7.9
=7.8×(2.1+7.9)
=7.8×10
=78=6.3÷(0.7×2)
=6.3 ÷0.7÷2
=9÷2
=4.5看谁算得又对又快 12.84＋0.75＋0.16 13.35-4.68+2.65
5.17－1.8－3.2 2.5×（4＋0.4）
（80－8）×125 0.25×8.5×4
7.4×0.28+0.28×2.6 0.25×36
0.125 ×2.5×3.2 0.85×99
9.36－(4.36－3.5) 76×0.08+0.2×7.6 看谁算得又对又快= 12.84 ＋0.16 ＋0.75
=13 ＋0.75
=13.75= 13.35+2.65-4.68
= 16-4.68
= 11.3212.84＋0.75＋0.16 13.35-4.68+2.655.17－1.8－3.2 2.5×（4＋0.4）（80－8）×125 0.25×8.5×4= 5.17－(1.8+3.2 )
= 5.17－5
= 0.17= 2.5×4＋2.5×0.4
=10 + 1
=11= 80 ×125 －8×125
=10000—1000
=9000= 0.25×4×8.5
= 1×8.5
= 8.5看谁算得又对又快7.4×0.28+0.28×2.6 0.25×360.125 ×2.5×3.2 9.36－(4.36－3.5) 0.85×99 76×0.08+0.2×7.6= (7.4+2.6)×0.28
=10 ×0.28
=2.8= 0.25×4×9
=1×9
=9= (0.125 ×8)+(0.4×2.5)
=1×1
=1= 0.85×(100—1)
=0.85×100—0.85×1
=85—085
=84.15= 9.36－4.36 + 3.5
= 5 + 3.5
= 8.5= 76×0.08+0.02×76
= 76×(0.08 + 0.02)
= 76×0.1
= 7.61.28×8.6+1.44×4.3 数学家的名言：没有大胆的猜测，就做不出伟大的发现。
——牛顿
数学中的一些美丽定理具有这样的特性:它们极易从事实中归纳出来, 但证明却隐藏的深。
——高斯
加法结合律是
乘法交换律是
乘法结合律是
乘法分配律是a+b=b+a(a+b)+c=a+(b+c)a×b=b×a(a×b) ×c=a×(b×c)(a+b) ×c=a×c+b×c
简便运算的复习先说说怎样算简便，再简便计算。 3.68＋0.6＋0.4 33.8＋6.2＋12.443.5＋12.72＋6.5＋2.28 53.6＋14.7＋5.3= 3.68＋(0.6＋0.4)
= 3.68＋1
=4.68= 40 + 12.4
= 52.4= (43.5 + 6.5) + (12.72 + 2.28)
= 50 + 15
= 65= 53.6 + (14.7 + 5.3)
= 53.6 + 20
= 73.6你能简便计算下面各题吗？16.45 – 3.7 – 6.3 4.02 – 1.8 + 1.985.9 + 0.1 - 5.9 + 0.1 13.64 - 2.8 - 3.64= 16.45 – (3.7 + 6.3)
= 16.45 –10
= 6.45= (4.02 + 1.98 )– 1.8
= 6 – 1.8
= 4.2=( 5.9 - 5.9 )+( 0.1 + 0.1 )
=0 + 0.2
= 0.2= 13.64 - 3.64 - 2.8
= 10 - 2.8
= 7.26.43 – (1.4 – 0.57） 9.36 – (4.36 – 3.5)= 6.43 – 1.4 + 0.57
= 6.43 + 0.57 – 1.4
= 7 – 1.4
= 5.6= 9.36 – 4.36 + 3.5
= 5 + 3.5
= 8.5先说说怎样算简便，再简便计算。7.4×8.3 + 1.7×7.4 0.125×0.25×8×4 9.43×99 + 9.43 25×3.2×1.25= 7.4×8.3 + 1.7×7.4
= 7.4×(8.3 + 1.7)
= 7.4×10
=74=(0.125×8)×(0.25×4)
=1×1
=1= 9.43×(99 + 1)
= 9.43×100
=943= (25×0.4 )×(8 ×1.25)
=10×10
=100你能简便计算下面各题吗？47500÷2.5÷4 26.4 ÷（6×0.4）= 47500÷（2.5×4）
= 47500×10
=4750= 26.4 ÷6 ÷ 0.4
=4.4 ÷ 0.4
=116.1×0.99= 6.1×(1 – 0.01)
= 6.1×1 – 6.1×0.01
= 6.1 – 0.061
= 6.039 85×8÷85×8 7.8×2.1+78×0.79 6.3÷1.4= 85÷85×8×8
=1×8×8
=64= 7.8×2.1+7.8×7.9
=7.8×(2.1+7.9)
=7.8×10
=78=6.3÷(0.7×2)
=6.3 ÷0.7÷2
=9÷2
=4.5看谁算得又对又快 12.84＋0.75＋0.16 13.35-4.68+2.65
5.17－1.8－3.2 2.5×（4＋0.4）
（80－8）×125 0.25×8.5×4
7.4×0.28+0.28×2.6 0.25×36
0.125 ×2.5×3.2 0.85×99
9.36－(4.36－3.5) 76×0.08+0.2×7.6 看谁算得又对又快= 12.84 ＋0.16 ＋0.75
=13 ＋0.75
=13.75= 13.35+2.65-4.68
= 16-4.68
= 11.3212.84＋0.75＋0.16 13.35-4.68+2.655.17－1.8－3.2 2.5×（4＋0.4）（80－8）×125 0.25×8.5×4= 5.17－(1.8+3.2 )
= 5.17－5
= 0.17= 2.5×4＋2.5×0.4
=10 + 1
=11= 80 ×125 －8×125
=10000—1000
=9000= 0.25×4×8.5
= 1×8.5
= 8.5看谁算得又对又快7.4×0.28+0.28×2.6 0.25×360.125 ×2.5×3.2 9.36－(4.36－3.5) 0.85×99 76×0.08+0.2×7.6= (7.4+2.6)×0.28
=10 ×0.28
=2.8= 0.25×4×9
=1×9
=9= (0.125 ×8)+(0.4×2.5)
=1×1
=1= 0.85×(100—1)
=0.85×100—0.85×1
=85—085
=84.15= 9.36－4.36 + 3.5
= 5 + 3.5
= 8.5= 76×0.08+0.02×76
= 76×(0.08 + 0.02)
= 76×0.1
= 7.61.28×8.6+1.44×4.3 数学家的名言：没有大胆的猜测，就做不出伟大的发现。
——牛顿
数学中的一些美丽定理具有这样的特性:它们极易从事实中归纳出来, 但证明却隐藏的深。
——高斯