Answer:
Step-by-step explanation:
Ten thousands = 10,000 * 1 = 10,000
2 thousands = 1000 * 2 = 2000
7 hundreds = 100 * 7 = 700
8 tens = 10 * 8 = 80
9 ones = 1 * 9 = 9
<u>Adding them all:</u>
=> 10,000 + 2,000 + 700 + 80 + 9
=> 12,789
Hope this helped!
<h2>~AnonymousHelper1807</h2>