Help me develop a Function in Apple Numbers

[Alex Taylor]

I need help in developing an algorith in numbers.

Suppose i have 4 columns.
1st one is Checklist - A
2nd is Quantity - B
3rd contains Prices D
4th one is Total

I have developed a SUMIF function so when i am marking tick on the checklist it is summing up the prices in total. The function looks like =SUMIF(A,TRUE,D)

But i want to multiply the prices with quantity and the total should generate for the checklist i mark tick.

Please help me with this

 

[Alex Taylor]

answer me mi