人教版六年级数学书上册练习十一全部答案

5/7x=35

x=49

方法2 35÷5/7=49(第页)

2.方法1:解法:假设一个成年人每天需要大约x克的钙。

3/8x=3/10

x=4/5

方法2: 3/10 ÷ 3/8 = 4/5 (g)

3.解1解:假设飞船速度为x km/s。

40/57x=8

40/57x÷40/57=8÷40/57

x=57/5

解2 8÷40/57=57/5(公里/秒)

解:让这个桶重X公斤。

x-1/10x=9

(1-1/10)x=9

x=9÷9/10

x=10

方法29÷(1-1/10)= 10(kg)。

5.15/16÷3=15/16×1/5=3/16 12/25÷8=12/25×1/8=3/50

8÷4/5=8×4/5=10 21/40÷7/8=21/40×8/7=3/5

16÷2/17=16×17/2=136 7/24÷6/49=7/24×17/2=343/144

18/35÷0.6×2/3 4/9×15/16÷5/6

=35/18 ×10/6×2/3 =5/12×6/5

=6/7× 2/3 =1/2

=12/21=4/7

( 2-0.6)÷7/15 35/64÷(1/8+3/4)

=1.4×15/7 =35/64÷7/8

=3 =35/64×8/7

=5/8

6.(1500+1000)×3/5 = 1500(元)

7.48+48÷4/5=108(万单位)

8.5200÷52/55=5500(公里

9.(1) 24 ÷ 1/2 = 48(个)

一等奖:48× 1/6 = 8(枚)

二等奖:48× 1/3 = 16(枚)

(2) 48÷120=2/5

10.3/5x = 25/72 8/9x = 1/6×16/51

3/5x÷3/5 = 25/72÷3/5 8/9x÷8/9 = 8/153÷8/9

x = 125/216 x = 1/17

x÷6/35=26/45÷13/25

x÷6/35×6/35=10/9×6/35

x=4/21

11.2/5÷4 = 1/10(1-2/5)÷1/10 = 6(汽车)

12.(1) 28 ÷ 1/5 = 140(个)

(2)80÷(1-4/5)=400(周)

13.1804÷39/40≈1850(万吨)

14.解:假设河南大约有X百万人。

x-1/46=9000

(1-1/46)x=9000

45/46x=9000

45/46乘以45/46=9000乘以45/46

x=9200