Answer:
The answer is r < or equal to 15.5.
Step-by-step explanation:
1block=2cm
1cm=10mm
therefore 1block=2×10=20
1000÷20=50
=50blocks
8n - 3.9
Given
- (- 8n + 3.9 ) ← multiply each term in the parenthesis by - 1
= 8n - 3.9