Maths Puzzles

Carla was enjoying her new calculator and discovering all its features and functions. She accidentally multiplied a number by 5 when she should have divided by 5. The incorrect answer displayed was 75. What should have been the correct answer?   Find the solution here . 

Two friends were playing a ring toss game where you throw 10 rings over the tops of cylinders 15 feet away.  For each ring that goes over a cylinder, you receive 5 points. For each ring that misses, you lose 3 points.  One of the friends scored 26 and the other scored 18. How many rings did each have that were successful tosses?   Find the solution here . 

Five children share some sweets equally. They eat 8 sweets and save some for later. The number of sweets left together is equal to the number of sweets each child received in the beginning.  How many sweets did each child receive?   Solution: Let us say each child received x sweets.  And each child saved y sweets.  So total number of sweets saved by all children = 5 *(x-8) But this number is equal to the number of sweets received by each child. So x  =  5(x-8) x = 5x-40 40 = 4x x  = 10 Each child received 10 sweets.   

  Solution : If you take 635 as a, the first product  - a * (a+1) = a 2 +a Second product - (a-1) * (a+3) = a 2 -a+3a-3 = a 2 +2a-3 So second product  - 634*638 is larger.