total 7+ 2 = 9 Zaidi's savings = 7/9's of $3600 Khairi's savings = 2/9's of $3600
[ Note the word 'of' is often used in maths to imply 'multipication' i.e. 1/3 of 200] Zaidi's savings = 7/9 x $3600= $2800 Khairi's savings = 2/9 x $3600 = $800 You can check your answer by adding the two amounts together: $2800 + $800 = $3600.
