Challenge your observation skills with this optical illusion by finding the hidden number ’78’ among numerous ’70s’ within 7 seconds. Discover how optical illusions entertain, improve concentration, and sharpen problem-solving abilities. Tips are provided to help you get better at spotting hidden details in such tricky puzzles. Challenge your observation skills with this optical illusion by finding the hidden number ’78’ among numerous ’70s’ within 7 seconds. Discover how optical illusions entertain, improve concentration, and sharpen problem-solving abilities. Tips are provided to help you get better at spotting hidden details in such tricky puzzles. Health and Fitness, Health Tips, Exercises & Workout Tips, Diet & Wellness | Times of India Lifestyle