Metamath Proof Explorer
		
		
		
		Description:  Comparing two decimal integers with three "digits" (unequal higher
         places).  (Contributed by AV, 8-Sep-2021)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypotheses | 3decltc.a | ⊢ 𝐴  ∈  ℕ0 | 
					
						|  |  | 3decltc.b | ⊢ 𝐵  ∈  ℕ0 | 
					
						|  |  | 3decltc.c | ⊢ 𝐶  ∈  ℕ0 | 
					
						|  |  | 3decltc.d | ⊢ 𝐷  ∈  ℕ0 | 
					
						|  |  | 3decltc.e | ⊢ 𝐸  ∈  ℕ0 | 
					
						|  |  | 3decltc.f | ⊢ 𝐹  ∈  ℕ0 | 
					
						|  |  | 3decltc.3 | ⊢ 𝐴  <  𝐵 | 
					
						|  |  | 3declth.1 | ⊢ 𝐶  ≤  9 | 
					
						|  |  | 3declth.2 | ⊢ 𝐸  ≤  9 | 
				
					|  | Assertion | 3declth | ⊢  ; ; 𝐴 𝐶 𝐸  <  ; ; 𝐵 𝐷 𝐹 | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 3decltc.a | ⊢ 𝐴  ∈  ℕ0 | 
						
							| 2 |  | 3decltc.b | ⊢ 𝐵  ∈  ℕ0 | 
						
							| 3 |  | 3decltc.c | ⊢ 𝐶  ∈  ℕ0 | 
						
							| 4 |  | 3decltc.d | ⊢ 𝐷  ∈  ℕ0 | 
						
							| 5 |  | 3decltc.e | ⊢ 𝐸  ∈  ℕ0 | 
						
							| 6 |  | 3decltc.f | ⊢ 𝐹  ∈  ℕ0 | 
						
							| 7 |  | 3decltc.3 | ⊢ 𝐴  <  𝐵 | 
						
							| 8 |  | 3declth.1 | ⊢ 𝐶  ≤  9 | 
						
							| 9 |  | 3declth.2 | ⊢ 𝐸  ≤  9 | 
						
							| 10 | 1 3 | deccl | ⊢ ; 𝐴 𝐶  ∈  ℕ0 | 
						
							| 11 | 2 4 | deccl | ⊢ ; 𝐵 𝐷  ∈  ℕ0 | 
						
							| 12 | 1 2 3 4 8 7 | declth | ⊢ ; 𝐴 𝐶  <  ; 𝐵 𝐷 | 
						
							| 13 | 10 11 5 6 9 12 | declth | ⊢ ; ; 𝐴 𝐶 𝐸  <  ; ; 𝐵 𝐷 𝐹 |