1/4+7/16+7/4=4/16+7/16+28/16=4+7+28/16=39/16
1/4 + 7/16 + 7/4 = 4/16 + 7/16 + 28/16 = 39/16
Chi can may tinh la xong dap an ra 39/16
1/4 + 7/16 + 7/4
= { 1/4 + 7/4 } + 7/16
= 8/4 + 7/16
= 32/16 + 7/16
= 39/16
Vì : 16 chia hết cho 4 nên:
=>Ta chọn 16 làm mẫu số chung
~~~~tự làm...(vì tớ học lớp 6 nên ko rõ lắm về tiểu học~~~~~~~
=> \(\frac{1}{4}+\frac{7}{16}+\frac{7}{4}=\frac{39}{16}\)
\(\frac{1}{4}+\frac{7}{16}+\frac{7}{4}\)
=\(\left(\frac{1}{4}+\frac{7}{4}\right)+\frac{7}{16}\)
= \(2+\frac{7}{16}\)
\(\frac{39}{16}\)
Ta nhóm:\(\frac{1}{4}+\frac{7}{4}=2+\frac{7}{16}\)\(=\frac{36}{16}\)
\(=\left(\frac{1}{4}+\frac{7}{4}\right)+\frac{7}{16}=\frac{8}{4}+\frac{7}{16}=2+\frac{7}{16}=2\frac{7}{16}\)