The mass of a papaya is $2\frac{1}{4}$ kg. The mass of a jackfruit is $3$ times the mass of a papaya. What is the total mass of the papaya and the jackfruit?     Below is James\textquotesingle s workings.  $2\frac{1}{4} \times 4$ = $2\frac{4}{4}$ = $3$.  The total mass is $3$kg.     Are his workings correct? If not, circle his error and find the correct answer. 
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