1-1/4-1/7-3/14=11/28(hạt cà phê)

C

steak?

1. He said he was a student.

2. This school was completed in 1990.
3. She asked if I knew Japan.

4.I was given a book by Nam at the party.

C

Lượng xăng dầu nhập khẩu từ Hàn Quốc chiếm số phần tổng lượng xăng dầu cả nước là:

1-\(\dfrac{1}{3}\)-\(\dfrac{1}{5}\)=\(\dfrac{7}{15}\)(tổng lượng xăng dầu cả nước)

Đáp số:\(\dfrac{7}{15}\)tổng lượng xăng dầu cả nước

Sơn Tinh Thủy Tinh

A

a)25.(-3).4.(-7)

=(25.4).(-3).(-7)

=100.(-3).(-7)

=(-300).(-7)

=2100

b)\(\dfrac{3}{5}\)+\(\dfrac{-5}{9}\)

=\(\dfrac{27}{45}\)+\(\dfrac{-25}{45}\)

=\(\dfrac{2}{45}\)

c)S=\(\dfrac{27}{23}\)+\(\dfrac{-5}{21}\)-\(\dfrac{4}{23}\)+\(\dfrac{-16}{21}\)+\(\dfrac{1}{2}\)

S=(\(\dfrac{27}{23}\)-\(\dfrac{4}{23}\))+(\(\dfrac{-5}{21}\)+\(\dfrac{-16}{21}\))+\(\dfrac{1}{2}\)

S=1+(-1)+\(\dfrac{1}{2}\)

S=\(\dfrac{1}{2}\)