21,71+4,06*у=27,8

To solve the equation \( 21.71 + 4.06y = 27.8 \), follow these steps:

1. Isolate the term with \( y \): Subtract \( 21.71 \) from both sides:

   \[ 4.06y = 27.8 - 21.71 \]

   Calculate the right side:

   \[ 27.8 - 21.71 = 6.09 \]

   Now the equation is:

   \[ 4.06y = 6.09 \]

2. Solve for \( y \): Divide both sides by \( 4.06 \):

   \[ y = \frac{6.09}{4.06} \]

   Now, calculate \( y \):

   \[ y \approx 1.5 \]

So the solution is:

\[ y \approx 1.5 \]