Question
What are the missing numbers?
1377, 2487, (a) _____, 2509, (b) _____, 2531
1 m
(a)

Click button first when a symbol is required. X

(b)

Click button first when a symbol is required. X

What are the missing numbers?
1377, 2487, (a) _____, 2509, (b) _____, 2531