Question

Jasmine is 5 years younger than twice her sister's age. If the sum of jasmine and her sister's age is 61, how old are the girls?

Answer 1

jasmine is 39, her sister is 22

Explanation:

let j be jasmine's age and s be her sister's age. we can set up these two formulas:

2s - 5 = j

j + s = 61

replace j in the second formula with 2s - 5:

2s - 5 + s = 61

simplify: 3s - 5 = 61

add 5 to each side: 3s = 66

divide each side by 3: s = 22

now replace s with 22 in the first formula:

2(22) - 5 = j

multiply: 44 - 5 = j

subtract: 39 = j