Solve 15500=31/2(140*2+30d)

$$15500 = \frac { 31 } { 2 } ( 140 \times 2 + 30 d )$$

Solve for d

$$d=24$$

Steps for Solving Linear Equation

Multiply both sides by \frac{2}{31}, the reciprocal of \frac{31}{2}.

$$15500\times \frac{2}{31}=140\times 2+30d$$

Express 15500\times \frac{2}{31} as a single fraction.

$$\frac{15500\times 2}{31}=140\times 2+30d$$

Multiply 15500 and 2 to get 31000.

$$\frac{31000}{31}=140\times 2+30d$$

Divide 31000 by 31 to get 1000.

$$1000=140\times 2+30d$$

Multiply 140 and 2 to get 280.

$$1000=280+30d$$

Swap sides so that all variable terms are on the left hand side.

$$280+30d=1000$$

Subtract 280 from both sides.

$$30d=1000-280$$

Subtract 280 from 1000 to get 720.

$$30d=720$$

Divide both sides by 30.

$$d=\frac{720}{30}$$

Divide 720 by 30 to get 24.

$$d=24$$