Mix and Yield variance analysis-Lecture example -1 BPP notes

I have studied variance analysis in my graduation using formulas :
Material Mix Variance : Standard cost for actual input – actual quantity at standard price
Material Yield Variance : Standard cost for actual output – Standard cost for actual input.

Using this formula when I do Lecture example-1 of BPP notes :

Ques- Brenda and Eddie are analysing the main ingredients to their basic pasta sauce.
The standard ingredients for one batch of tomato pasta sauce are:
$
Onions 5kg @ $2/kg 10
Tomatoes 5kg @ $4/kg 20
30
During June, 100 batches of sauce were prepared, using the following ingredients:
Onions 600 kg
Tomatoes 900 kg
For the total materials mix and total materials yield variance, was there a favourable or adverse result in June?

I get mix variance correct but yield variance incorrect.

Can you help me with my formula to solve this Question?