Explanation:
31) 1 1/4 × 8/9
multiply the denominator(4) with 1 which is 4 itself, then add 4 with the numerator(1) which is 5. therefore you will get,
⇒5/4 × 8/9
⇒ 5×8/4×9
⇒40/36
⇒10/9
32) 2/3 × 2 1/4
multiply the denominator(4) with 2 which is 8, then add 8 with the numerator(1) which is 9. therefore you will get,
⇒2/3 × 9/4
⇒2×9/3×4
⇒18/12
⇒3/2
33) 2 2/9 × 3/4
multiply the denominator(9) with 2 which is 18, then add 18 with the numerator(2) which is 20. therefore you will get,
⇒20/9 × 3/4
⇒20×3/9×4
⇒60/36
⇒5/3
34) 4/5 × 2 11/12
⇒4/5 × 35/12
⇒4×35/5×12
⇒140/60
⇒7/3
35) 3 1/21 × 3/8
⇒64/21 × 3/8
⇒64×3/21×8
⇒192/168
⇒8/7
36) 1 1/5 × 3 1/4
⇒6/5 × 13/4
⇒6×13/5×4
⇒78/20
⇒39/10
37) 1 1/4 × 2 2/3
⇒5/4 × 8/3
⇒5×8/4×3
⇒40/12
⇒10/3
38) 1 1/5 × 3 3/4
⇒6/5 × 15/4
⇒6×15/5×4
⇒90/20
⇒9/2
39) 3 2/7 × 2 5/8
⇒23/7 × 21/8
⇒23×21/7×8
⇒483/56
⇒69/8
40) 3 1/9 × 2 1/7
⇒28/9 × 15/7
⇒28×15/9×7
⇒420/63
⇒20/3
hope it helps you!!