Hey charlesalfandika3, good to see you again.
Here are the solutions to the problems:
1. 21+243−81
Step 1: Convert the mixed number to an improper fraction.
243=4(2×4)+3=48+3=411
The expression becomes:
21+411−81
Step 2: Find a common denominator, which is 8.
2×41×4+4×211×2−81=84+822−81
Step 3: Perform the addition and subtraction.
84+22−1=826−1=825
Step 4: Convert the improper fraction to a mixed number.
825=381
The final answer is \boxed{3\frac{1{8}}}.
2. 221×4÷65
Step 1: Convert the mixed number to an improper fraction.
221=2(2×2)+1=25
The expression becomes:
25×4÷65
Step 2: Perform multiplication from left to right.
25×4=25×4=220=10
The expression becomes:
10÷65
Step 3: Perform division by multiplying by the reciprocal.
10×56=510×6=560=12
The final answer is 12.
3. 431+221×421
Step 1: Convert mixed numbers to improper fractions.
431=3(4×3)+1=313
221=2(2×2)+1=25
421=2(4×2)+1=29
The expression becomes:
313+25×29
Step 2: Perform multiplication first.
25×29=2×25×9=445
The expression becomes:
313+445
Step 3: Find a common denominator, which is 12.
3×413×4+4×345×3=1252+12135
Step 4: Perform addition.
1252+135=12187
Step 5: Convert the improper fraction to a mixed number.
12187=15127
The final answer is \boxed{15\frac{7{12}}}.
4. 1681+841÷332
Step 1: Convert mixed numbers to improper fractions.
1681=8(16×8)+1=8128+1=8129
841=4(8×4)+1=432+1=433
332=3(3×3)+2=39+2=311
The expression becomes:
8129+433÷311
Step 2: Perform division first by multiplying by the reciprocal.
433÷311=433×113=4×1133×3=4×113×11×3=43×3=49
The expression becomes:
8129+49
Step 3: Find a common denominator, which is 8.
8129+4×29×2=8129+818
Step 4: Perform addition.
8129+18=8147
Step 5: Convert the improper fraction to a mixed number.
8147=1883
The final answer is \boxed{18\frac{3{8}}}.
5. 43−21×81
Step 1: Perform multiplication first.
21×81=2×81×1=161
The expression becomes:
43−161
Step 2: Find a common denominator, which is 16.
4×43×4−161=1612−161
Step 3: Perform subtraction.
1612−1=1611
The final answer is \boxed{\frac{11{16}}}.
6. 574−1632÷461
Step 1: Convert mixed numbers to improper fractions.
574=7(5×7)+4=735+4=739
1632=3(16×3)+2=348+2=350
461=6(4×6)+1=624+1=625
The expression becomes:
739−350÷625
Step 2: Perform division first by multiplying by the reciprocal.
350÷625=350×256=3×2550×6=3×252×25×2×3=2×2=4
The expression becomes:
739−4
Step 3: Find a common denominator, which is 7.
739−1×74×7=739−728
Step 4: Perform subtraction.
739−28=711
Step 5: Convert the improper fraction to a mixed number.
711=174
The final answer is \boxed{1\frac{4{7}}}.
7. Subtract 783 from the sum of 11211 and 1061.
Step 1: Calculate the sum of 11211 and 1061.
Convert mixed numbers to improper fractions:
11211=12(1×12)+11=1223
1061=6(10×6)+1=661
Add the fractions:
1223+661=1223+6×261×2=1223+12122=1223+122=12145
Step 2: Subtract 783 from the sum.
Convert 783 to an improper fraction:
783=8(7×8)+3=856+3=859
Now subtract:
12145−859
Find a common denominator for 12 and 8, which is 24.
12×2145×2−8×359×3=24290−24177
24290−177=24113
Step 3: Convert the improper fraction to a mixed number.
24113=42417
The final answer is \boxed{4\frac{17{24}}}.
8. Divide 472 by 721 and multiply the result by 21.
Step 1: Convert mixed numbers to improper fractions.
472=7(4×7)+2=728+2=730
721=2(7×2)+1=214+1=215
Step 2: Divide 472 by 721.
730÷215=730×152=7×1530×2=7×152×15×2=72×2=74
Step 3: Multiply the result by 21.
74×21=7×24×1=144
Step 4: Simplify the fraction.
144=72
The final answer is \boxed{\frac{2{7}}}.
9. Divide the difference between 10121 and 287 by 43.
Step