Aditi, Becky and Cali collect coins. Aditi has 6 more coins than Becky. Cali has 1 less coin than Aditi. Altogether they have 71 coins. How many coins do they each have? Show all your working.
Form 3 equations. Equation 1: A= 6+ B.Equation 2 : C= A-1. Equation 3: A+ B+ C= 71.Substitute equation 1 and 2 into 3 to get: 6+ B + B + A - 1= 71 -> 2B + A= 66 which is equation 4. Then, substitute equation 1 into equation 4: 2B+6+B=66-> 3B=60. So, B=20Substitute B into 1 to get A: A= 20+6= 26. Substitute A into equation 2 to get C. So, C=25
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