Hi umakanthu1990. In answer to your question, I can only repeat the first half of my hub, with a few editor's notes from me.
Basically, the intelligence quotient is a measurement of people's cognitive abilities and tests their skills to use reason and logic to make decisions.
IQ is the ratio multiplied by 100 of the mental age of a subject as reported on a standardized test to the chronological age. IQ is primarily used to measure the ability to reason through a given problem/scenario; the ability to apply conceptual knowledge to one's current situations.
Contrastingly, the efficiency quotient takes into account many, many other factors that affect how one acts in a given scenario, and recognizes that sometimes the most "logical" solutions (pure reasoning) may not be the most appropriate. In short, it's one's "emotional intelligence."
Emotional intelligence skills include but are not limited to empathy, intuition, creativity, flexibility, resilience, stress management, leadership, integrity, authenticity, and interpersonal skills.
For instance, those with high IQs may be able to understand quantum mechanics, but if they have a low EQ, they may not be able to successfully share this knowledge with others because they do not know how to interact with them.
Moreover, one's efficiency quotient is much more difficult to measure than one's IQ, as it often goes beyond standardized testing.
I hope this helps. My hub on this topic is meant merely as a primer, and I encourage you to seek out other perspectives on this topic, as my background is in communication and others will be able to give you a far more scientific explanation than I could, if you so desire.
Thank you for reading, and I hope you have a lovely day!