# Highlighted step

#### Joseph Graydon

##### New member

Hi, can anyone show me how 4% is arrived at in the highlighted step in this image? I understand the rest of the problem fine.

#### Joseph Graydon

##### New member

I have a similar question regarding solving for the value of W in this problem. I don't understand how to solve algebraically for these answers.

#### Jomo

##### Elite Member
Try to solve the equation for the lamda, show us your work and someone will help you. We do not solve problems for students on this forum. Rather we help students solve their own problems.

#### Joseph Graydon

##### New member
Thanks Jomo - I had no workings bc I didn't understand what needed to be done to progress in solving the problem. Perhaps I should have asked what methods to follow. I found another source that explains the algebraic method though. Thanks for the response though!

#### Jomo

##### Elite Member
Sure you can solve this linear equation.

0.078 = (0.07 - x) + 1.2x
0.078 = 0.07 + .2x
0.008 = .2x
0.04 = x. So x = 4%.

#### Joseph Graydon

##### New member
Thanks - I understand about combining common terms etc now, pretty simple once you think about it. Embarrasing lol