Greta received 10 more letters in the mail than her brother. Greta's mother received twice the total number of letters Greta and her brother received. Calculate the total number of letters the three received if Greta's brother received 40 letters.
How many letters did Greta receive? ** Since Greta's brother received 40 letters, Greta received 40+10 = <<40+10=50>>50 letters.
How many letters did Greta and her brother receive? ** Together, Greta and her brother received 50 + 40 = <<50+40=90>>90 letters.
How many letters did Greta's mother receive? ** Greta's mother received twice the total number of letters Greta and her brother received, which totals 90*2 = <<90*2=180>>180 letters.
How many letters did Greta, her brother, and her mother receive? ** In total, the three received 90+180 = <<90+180=270>>270 letters.
#### 270