Could you please tell me whether the math questions that I rewrite are correct or not? Does total boys in the class means count all the boys in the class? Can I write "number of boys in the class" instead of "total number of boys in the class"? ...

Could you please tell me whether the math questions that I rewrite are correct or not?

Mrs Aris had 9kg 500g of rice at the begining of a month. She used 2kg 750g of it in the first week and 3kg 300g in the second week. "How much rice did she have left at the start of the third week?"

"How much rice did she she have at the start of the third week?"

Mrs Nathan bought a printer for $200. She used 3/8 of the amount left to buy some books. "If she had $600 at first, find the amount she had left in the end."

"If she had $600 at first, find the amount that she had in the end."

Mrs Wee prepared a cake. Her family ate 1/5 of the cake. 1/2 of the remaining cake was eaten by her friends. "If the mass of the cake left was 240g, find the total mass of the cake eaten."

"If the mass of the remaining cake was 240g, find the total mass of the cake eaten."

Mrs Gek had 2800g of sugar. She used 1/7 of it to make a cake and 2/7 of it to bake some cookies. "Find the mass of sugar Mrs Gek had left after making the cakes and cookies."

"Find the mass of sugar that Mrs Gek had after making the cake and cookies."

Does total boys in the class mean count all the boys in the class?

Total boys = 24

Can I write "number of boys in the class" instead of "total number of boys in the class."

Number of boys in the class = 24