A = 38,27 x 2,5 + 23,45 x 19 - 1,25 + 19 x 1,55

A = 95,675 + 445,55 - 1,25 + 29,45

A = 569,425

A= 38,27 x 2,5 + 23,45 x 19 - 0,54 x 1,25 + 19 x 1,55

A= 95,675 + 445,55 - 0,675 + 29,45

A= 541,225 - 0,675 + 29,45

A= 540,55 + 29,45

A= 570

A = 38,27 x 2,5 + 23,45 x 19 ‐ 1,25 + 19 x 1,55

A = 95,675 + 445,55 ‐ 1,25 + 29,45

A = 569,425 

A = 95,675 + 445,55 - 0,675 + 29,45

A = 570

19 (23,45+1,55)+95 =570

đầy đủ từng bước

\(\text{a)4,38-19+0,62}\)\(=-14\)

\(b.3,45-5,7+8,55=6,3\)

\(c.14,7+\left(-8,4\right)+\left(-4,7\right)=1.6\)

2.

\(a,-2,4-\left(0,54-2,5\right)=-0,44\)

\(b,-25,4-\left(5,54-2,5\right)=-28,44\)

\(c.2,15-\left(-0,6+0,12\right)=2.63\)

a, \(\frac{2}{3}\).\(\frac{15}{17}\)+\(\frac{2}{3}\).\(\frac{2}{17}\)

= \(\frac{2}{3}\).( \(\frac{15}{17}\)+ \(\frac{2}{17}\))

= \(\frac{2}{3}\). 1

=\(\frac{2}{3}\)

b,\(\frac{20}{19}\):\(\frac{3}{7}\)- \(\frac{1}{19}\): \(\frac{3}{7}\)

= ,\(\frac{20}{19}\).\(\frac{7}{3}\)- \(\frac{1}{19}\).\(\frac{7}{3}\)

= \(\frac{7}{3}\).(\(\frac{20}{19}\)-\(\frac{1}{19}\))

=\(\frac{7}{3}\).1

=\(\frac{7}{3}\)

Mn đã trả lời rùi mà~

A. \(\frac{2}{3}.\frac{15}{17}+\frac{2}{3}.\frac{2}{17}\)

=\(\frac{2}{3}.\left(\frac{15}{17}+\frac{2}{17}\right)\)

=\(\frac{2}{3}.1\)

=\(\frac{2}{3}\)

B. \(\frac{20}{19}:\frac{3}{7}-\frac{1}{19}:\frac{3}{7}\)

=\(\left(\frac{20}{19}-\frac{1}{19}\right):\frac{3}{7}\)

=1:\(\frac{3}{7}\)

=\(\frac{7}{3}\)