Question

[Juna]

x x 280 : 25 - 7,2 = 15

Answer 1

[ILoveMath]

\(x\times280:25-7,2=15\\ \Rightarrow x\times11,2=22,2\\ \Rightarrow x=\dfrac{111}{56}\)

Answer 2

[Juna]

( x+4 ) + (x+6 ) + (x+8) + ...+(x+26) = 210