Giải bài tập SGK toán lớp 4.Tiết 38. Luyện tập chung trang 48 SGK Toán 4

    Bài 1:

.Tính rồi thử lại:

a) $35269+27485$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">35269</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">+</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">27485</span></span>}$                              

    $80326-45719$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">80326</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">-</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">45719</span></span>}$                                     

b) $48796+63584$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">48796</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">+</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">63584</span></span>}$

    $10000-8989$

$\mathrm{Đáp\; án:}$

a) +) $35269+27485=62754$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">35269</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">+</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">27485</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">=</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">62754</span></span>}$

         Thử lại: $62754-27485=35269$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">62754</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">-</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">27485</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">=</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">35269</span></span>}$

    +) $80326-45719=34607$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">80326</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">-</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">45719</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">=</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">34607</span></span>}$

         Thử lại: $34607+45719=80326$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">34607</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">+</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">45719</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">=</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">80326</span></span>}$

b) +) $48796+63584=112380$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">48796</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">+</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">63584</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">=</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">112380</span></span>}$

         Thử lại: $112380-63584=48796$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">112380</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">-</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">63584</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">=</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">48796</span></span>}$

    +) $10000-8989=1011$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">10000</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">-</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">8989</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">=</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">1011</span></span>}$

        Thử lại: $1011+8989=10000$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">1011</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">+</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">8989</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">=</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">10000</span></span>}$

$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">10000</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">-</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">89</span></span>}$

    Bài 2. 

Tính giá trị của biểu thức:

a) $570-225-167+67$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">570</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">-</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">225</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">-</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">167</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">+</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">67</span></span>}$                 

    $168\times 2:6\times 4$$\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">168</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">\times </span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">2</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">:</span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">6</span></span>}<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">\times </span></span>\mathrm{<span\; style="font-family:arial,helvetica,sans-serif;"><span\; style="font-size:16px;">4</span></span>}$                             

b) $468:6+61Điều\; hướng\; bài\; viết$