Question

tinh nhanh

a,204-84:12

b,99-97+95-93+91-89+......+7-5+3-1

Answer 1

a. \(204-84:12\)

\(=204-7\)

\(=197\)

b. \(99-97+95-93+91-89+...+7-5+3-1\)

\(=\left(99-97\right)+\left(95-93\right)+\left(91-89\right)+...+\left(7-5\right)+\left(3-1\right)\)

\(=2+2+2+...+2+2\)

\(=2.25\)

\(=50\)

Answer 2

a. 204 - 84 : 12
=204 - 12 * 7 : 12
=204 - 1 * 7
=204 - 7
=197