Gee, my coffee is way too hot right now! How many minutes do I have to wait until it cools down to taste the best, then? How can I calculate the age of a bone of a dinosaur my friend found on the beach? What will be the population of the earth 10 years from now? Why does it take time for a TV set to display pictures when we turn it on? Will my house collapse due to an earthquake? ...Traveling with Math guru for three days, we will be surprised that the questions above raised in our daily life can be explained by differential equations. We can get the answers to many more questions as well as the ones above by solving differential equations. Learning engineering math, we don t want to simply hear words in lectures, just read letters and numbers in the books, and merely do the problem sets, but really want to: Actually and vividly picture what the questions are about See how the equations work doing real examples Get the point of the equations And have Fun doing the work.