We know that for every one and two thirds cups of flour, we add one cup of chocolate chips. If we divide one cup of chocolate chips by one and two thirds cups, we're going to find the amount of chocolate chips for every cup of flour.
Now we know that for every cup of flour, we haev 3/5 cups of chocolate chips.
To find the amount of chocolate chips when one and one quarter cups of flour is used, we just need to multiply this new ratio by one and one quarter.
And this is our answer.
When one and one quarter cups of flour is used, three quarters(3/4) of chocolate chips are used.