a, using them to wrap food

b, decorate it to make a flower vase, use it to keep pencls in

c, Swap them with my cousins and friends, give them to charity, wrap food

tick cho minh nha

Câu 2 :

a, \(\left(\dfrac{11}{12}+\dfrac{11}{12.23}+\dfrac{11}{23.34}+\dfrac{11}{34.45}+....+\dfrac{11}{89.100}\right)+x=\dfrac{2}{3}\)

\(\left(\dfrac{11}{1.12}+\dfrac{11}{12.23}+\dfrac{11}{23.34}+\dfrac{11}{34.45}+....+\dfrac{11}{89.100}\right)+x=\dfrac{2}{3}\)

\(\left(1-\dfrac{1}{12}+\dfrac{1}{12}-\dfrac{1}{23}+\dfrac{1}{23}-\dfrac{1}{34}+\dfrac{1}{34}-\dfrac{1}{45}+....+\dfrac{1}{89}-\dfrac{1}{100}\right)+x=\dfrac{2}{3}\)

\(\left(1-\dfrac{1}{100}\right)+x=\dfrac{2}{3}\)

\(\left(\dfrac{100}{100}-\dfrac{1}{100}\right)+x=\dfrac{2}{3}\)

\(\dfrac{99}{100}+x=\dfrac{2}{3}\)

\(x=\dfrac{2}{3}-\dfrac{99}{100}\)

\(x=\dfrac{200}{300}-\dfrac{297}{300}\)

\(x=\dfrac{-97}{300}\)

\(Vậy\) \(x=\dfrac{-97}{300}\)