PSLE
Tammy had to sew 180 vests. She sewed 7 vests each day from Monday to Friday and 12 each day on Saturday and Sunday. Starting on a Thursday, on which day of the week did Tammy finish sewing all the vests? Give your answer in number. (Eg Mon = 1)
Number of weekdays that Tammy sewed on the first week = 2

Number of vests that Tammy completed for from Thursday to Sunday on the first week
= 2 x 7 + 2 x 12 
= 14 + 24
= 38

Number of vests left to sew
= 180 - 38
= 142

Number of vests that Tammy could sew per week from second week onwards
= 5 x 7 + 2 x 12
= 35 + 24
= 59

Number of weeks that Tammy needed to sew 142 vests
= 142 ÷ 59
= 2 r 24

Number of days that Tammy needed to sew 24 vests
= 24 ÷ 7
= 3 r 3

Tammy needed 1 more day to finish sewing the remaining 3 vests.

Day of the week that Tammy completed her sewing
= 3 + 1
= 4 (Thu)

Answer(s): 4