Closer than most people guess: Brazil (8,499,400 km² km²) is only about 10%% larger than China (9,371,225 km² km²).
Brazil sits in South America, China in Asia. On the old Mercator map the latitude gap distorted how large each felt beside the other; at true size the answer is simply 1.1×.
The old map muddied it further: Mercator inflates Brazil about 1× and China about 1.6×, so on a Mercator-style map this pair appears 1.7× apart instead of the true 1.1×.
Brazil fits 1× into China.