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Metamath Proof Explorer

Theorem 9lt10

Description: 9 is less than 10. (Contributed by Mario Carneiro, 8-Feb-2015) (Revised by AV, 8-Sep-2021)

Ref Expression
Assertion 9lt10 ⊢ 9 < 10

Proof

Step Hyp Ref Expression
1 9re ⊢ 9 ∈ ℝ
2 1 ltp1i ⊢ 9 < 9 + 1
3 9p1e10 ⊢ 9 + 1 = 10
4 2 3 breqtri ⊢ 9 < 10