Register Now

Login

Lost Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

222-9+11+12:2*14+14 = ? ( )

Toán Lớp 7: a) 0,5 + 1/3 + 0,4 + 5/7 +1/6 – 4/35 b) 8/9 +1/72 – 1/56 – 1/42 – 1/30 -1/20 – 1/12 – 1/6 – 1/2

Tháng Một 23, 2023 Toán học 2 Comments 0 views

Toán Lớp 7: a) 0,5 + 1/3 + 0,4 + 5/7 +1/6 – 4/35
b) 8/9 +1/72 – 1/56 – 1/42 – 1/30 -1/20 – 1/12 – 1/6 – 1/2

Comments ( 2 )

  1. ngochuong2k2
    ngochuong2k2
    23 Tháng Một, 2023 at 10:58 sáng
    Reply
    a) 0,5 + 1/3 + 0,4 + 5/7 +1/6 – 4/35
    = 1/2 + 1/3 + 2/5 + 5/7 +1/6 – 4/35
    = (1/2 + 1/3 +1/6) +(2/5 +  5/7- 4/35)
    = (3/6 + 2/6 +1/6) +(14/55 +  25/35 – 4/35)
    = 1 + 1
    = 2
    b) 8/9 +1/72 – 1/56 – 1/42 – 1/30 -1/20 – 1/12 – 1/6 – 1/2
    = 8/9 +1/72 – (1/56 + 1/42 + 1/30 +1/20 + 1/12 + 1/6 + 1/2)
    = 8/9 +1/72 – (1/(7.8) + 1/(6.7) + 1/(5.6) +1/(4.5) + 1/(3.4) + 1/(2.3) + 1/(1.2))
    = 8/9 +1/72 – ( 1/(1.2) + 1/(2.3) + 1/(3.4) + 1/(4.5) + 1/(5.6) +1/(6.7) +1/(7.8))
    = 8/9 +1/72 – (1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8)
    = 8/9 +1/72 – (1-1/8)
    = 8/9 +1/72 – 7/8
    = 64/72 +1/72 – 63/72
    = 2/72
    = 1/36
    (Chúc bạn học tốt)
     

  2. ngoclankhue
    ngoclankhue
    23 Tháng Một, 2023 at 10:58 sáng
    Reply
    a) 0,5 + 1/3 + 0,4 + 5/7 + 1/6 – 4/35
    = 1/2 + 1/3 + 2/5 + 5/7 + 1/6 – 4/35
    =( 1/2 + 1/3 + 1/6) + ( 2/5 + 5/7 – 4/35)
    = ( 3/6 + 2/6 + 1/6) + ( 14/35 + 25/35 – 4/35)
    = 1 + 1
    = 2
    b) 8/9 + 1/72 – 1/56 – 1/42 – 1/30 – 1/20 – 1/12 – 1/6 – 1/2
    = ( 8/9 + 1/72 – 1/12 – 1/6- 1/2) – ( 1/56 + 1/42 + 1/30 + 1/20)
    = (64/72 + 1/72 – 6/72 – 12/72 -36/72) – ( 15/840+ 20/840+ 28/840+42/840)
    =11/72 – 1/8
    =11/72 – 9/72
    = 1/36

Leave a reply

222-9+11+12:2*14+14 = ? ( )

Khánh Giao

About Khánh Giao