回答: 5% 説明: 100% = 220 10% = #220/10# = 22 5% = #22/2# = 11 # "" 220 "の何パーセントが" 11 "ですか? # #=> x% "/" 220 = 11# #=> x / 100 xx 220 = 11# #=> x = cancel11xx(100)/ cancel(220)^(20)# #=> x = 100/20 = 5# # "したがって" 220 "の" 5% "は" 11# "です