SG chevron_right Primary 3 chevron_right Number and Algebra

Please tell me how to do the two questions

SG chevron_right Primary 4 chevron_right Number and Algebra

Hi, can someone help with this question?There were some passengers travelling in a train. After 52 passengers alighted and another 160 passengers boarded the train, there were three times as many passengers as before. How many passengers were there in the train at first?

SG chevron_right Primary 3 chevron_right Measurement

How to do working and get the answer

SG chevron_right Primary 4 chevron_right Number and Algebra

How to do this question

SG chevron_right chevron_right

Can someone solve this puzzle from Japan ?