[tex]\text {Laura = } 12 \text { years } 3 \text { months } [/tex]
[tex]\text {Lisa = } 11 \text { years } 7 \text { months } [/tex]
[tex]\text {Deborah = } 11 \dfrac{1}{2} \text { years } = 11 \text { years } 6 \text { months } [/tex]
[tex]\text {Elizabeth = } 11 \dfrac{1}{3} \text { years } = 11 \text { years } 4 \text { months } [/tex]
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Find Total :
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[tex]\text {Total = } 12 \text { yr } 3 \text { mth } + 11 \text { yr } 7 \text { mth } + 11 \text { yr} 6 \text { mth} +11 \text { yr } 4 \text { mth} [/tex]
[tex]\text {Total = } 45 \text { years } 20 \text { months } [/tex]
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Find Average :
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[tex]\text {Average = } (45 \text { years } 20 \text { months }) \div 4[/tex]
[tex]\text {Average = } 560 \text { months } \div 4[/tex]
[tex]\text {Average = } 140 \text { months } \div 4[/tex]
[tex]\text {Average = } 11 \text { years } 8 \text { months }[/tex]
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[tex]\bf \text {Answer : Average = } 11 \text { years } 8 \text { months }[/tex]
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