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and their differences is 
. What are the numbers?
. Write down the numbers.
. Find the numbers.
. The number b is equal to three quarters of the number a. What are the numbers?
. How old is John and Mark?
products in six hours. How many products does each machine make in one hour if they make 
products when the machine A is running for one hour and the machine B three hours?
for 
apples and 
oranges , and Laura paid for 
for 
apples and 
oranges. How many pennies does a kilo of apples and a kilo of oranges cost?
and 
. The sum of the numbers 
and 
is equal to the number 
and 
