Final answer:
To find how many calls Keiko has made, we can set up an equation using the given information.
Step-by-step explanation:
To calculate how many calls Keiko has made so far, we need to use the given information. We know that she has convinced only 18% of the people she called to donate. If she gets 12 out of the next 30 people she calls to donate, she'll barely break 25% for the day.
Let's set up an equation:
(x + 12) / (x + 30) = 0.25
where x is the number of calls Keiko has made so far.
By solving this equation, we can find the value of x.