$14×5+8=$
$12×4=$
$3×600=$
$80×3=$
$720÷9=$
$26÷2=$
$486+14=$
$576÷2=$
$2100÷3=$
$5×100=$
$21×3×0=$
$128-14=$
$56÷8=$
$600÷5=$
$350+80=$
$25×4=$
$28×3=$
$450÷3=$
$700÷2=$
$560÷8=$
$560÷4=$

解析：这些题目主要考查了基础的数学运算能力，包括乘法、除法、加法和减法。
答案：
$14×5+8$
$= 70 + 8$
$= 78$
$12×4 = 48$
$3×600 = 1800$
$80×3 = 240$
$720÷9 = 80$
$26÷2 = 13$
$486+14 = 500$
$576÷2 = 288$
$2100÷3 = 700$
$5×100 = 500$
$21×3×0 = 0$
$128-14 = 114$
$56÷8 = 7$
$600÷5 = 120$
$350+80 = 430$
$25×4 = 100$
$28×3 = 84$
$450÷3 = 150$
$700÷2 = 350$
$560÷8 = 70$
$560÷4 = 140$

$74-47=$
$99÷3=$
$125×4=$
$300+1070=$
$250×2×0=$
$2500×4=$
$72-35=$
$607+295\approx$
$300×6=$
$52÷4=$
$420÷2=$
$760÷4=$
$700×4=$
$600×7=$
$123×2=$
$465×0=$
$85÷5=$
$972-200=$
$850÷5=$
$520÷4=$
$540÷3=$

解析：
这些问题主要考查基础的数学运算能力，包括减法、除法、乘法、加法和估算。
答案：
$74 - 47 = 27$
$99 ÷ 3 = 33$
$125 × 4 = 500$
$300 + 1070 = 1370$
$250 × 2 × 0 = 0$
$2500 × 4 = 10000$
$72 - 35 = 37$
$607 + 295 \approx 900$ (估算，实际值为902，但估算到最近的百位数为900)
$300 × 6 = 1800$
$52 ÷ 4 = 13$
$420 ÷ 2 = 210$
$760 ÷ 4 = 190$
$700 × 4 = 2800$
$600 × 7 = 4200$
$123 × 2 = 246$
$465 × 0 = 0$
$85 ÷ 5 = 17$
$972 - 200 = 772$
$850 ÷ 5 = 170$
$520 ÷ 4 = 130$
$540 ÷ 3 = 180$

$9×500=$
$180+179=$
$54+28=$
$42×3=$
$1700-800=$
$90÷3=$
$180÷3=$
$300÷5=$
$930÷3=$
$800÷4=$
$96÷3=$
$2×330=$
$50×6=$
$680÷2=$
$620÷2=$
$6×800=$
$960÷3=$
$540÷9=$
$540+280=$
$860÷2=$
$760÷2=$

解析：这些题目都是基础的数学运算题目，包括乘法、加法、除法和减法。我们可以直接进行计算。
答案:
$9×500= 4500$
$180+179= 359$
$54+28= 82$
$42×3= 126$
$1700-800= 900$
$90÷3= 30$
$180÷3= 60$
$300÷5= 60$
$930÷3= 310$
$800÷4= 200$
$96÷3= 32$
$2×330= 660$
$50×6= 300$
$680÷2= 340$
$620÷2= 310$
$6×800= 4800$
$960÷3= 320$
$540÷9= 60$
$540+280= 820$
$860÷2= 430$
$760÷2= 380$