ercise 1.4 LOL.2.1 LO1.2.3 Do the following calculations without a calculator: . \( 38+57+12=(38+12)+57=50+57=107 \) b. \( 76+58+14+12= \) 2. \( 322+64+16+8= \) d. \( 528+382-28= \) 2. \( 23 \times 5 \times 3 \times 2= \) f. \( 25 \times 7 \times 2= \) 3. \( 25 \times 263 \times 3 \times 4= \) h. \( 150 \times 4+150 \times 6= \) i. \( 36 \times 37+36 \times 53= \) c. \( 63 \times(40-2)= \) j. \( 63 \times(30+2)= \) 1. \( 45 \times(100+30+2)= \) a. \( 87 \times 89 \times 0= \) n. \( 0 \times(236-137) \div 54= \) o. \( 476 \times(-14+27-13)= \)

**b. Calculation of \(76+58+14+12\):** 1. Group the numbers: \((76+14) + (58+12)\) 2. Compute the sums: \(76+14=90\) and \(58+12=70\) 3. Add the results: \(90+70=160\) --- **2. Calculation of \(322+64+16+8\):** 1. Group the numbers: \((322+8) + (64+16)\) 2. Compute the sums: \(322+8=330\) and \(64+16=80\) 3. Add the results: \(330+80=410\) --- **d. Calculation of \(528+382-28\):** 1. First add: \(528+382=910\) 2. Then subtract: \(910-28=882\) --- **2. Calculation of \(23 \times 5 \times 3 \times 2\):** 1. Multiply in a convenient order: \(5 \times 2=10\) 2. Multiply the other pair: \(23 \times 3=69\) 3. Then multiply the results: \(69 \times 10=690\) --- **f. Calculation of \(25 \times 7 \times 2\):** 1. Multiply \(25 \times 2=50\) 2. Then multiply: \(50 \times 7=350\) --- **3. Calculation of \(25 \times 263 \times 3 \times 4\):** 1. Group the factors: \(25 \times 4=100\) and \(263 \times 3=789\) 2. Multiply the results: \(100 \times 789=78900\) --- **h. Calculation of \(150 \times 4 + 150 \times 6\):** 1. Factor out \(150\): \(150(4+6)\) 2. Compute the sum in the parentheses: \(4+6=10\) 3. Multiply: \(150 \times 10=1500\) --- **i. Calculation of \(36 \times 37 + 36 \times 53\):** 1. Factor out \(36\): \(36(37+53)\) 2. Compute the sum: \(37+53=90\) 3. Multiply: \(36 \times 90=3240\) --- **c. Calculation of \(63 \times (40-2)\):** 1. Compute the expression in parentheses: \(40-2=38\) 2. Multiply: \(63 \times 38\). Compute using distribution: \(63\times38=(60\times38)+(3\times38)=2280+114=2394\) --- **j. Calculation of \(63 \times (30+2)\):** 1. Compute the sum in the parentheses: \(30+2=32\) 2. Multiply: \(63 \times 32\). Compute using distribution: \(63\times32=(60\times32)+(3\times32)=1920+96=2016\) --- **1. Calculation of \(45 \times (100+30+2)\):** 1. Compute the sum in the parentheses: \(100+30+2=132\) 2. Multiply: \(45 \times 132\). Compute as: \(45\times132=(45\times100)+(45\times32)=4500+1440=5940\) --- **a. Calculation of \(87 \times 89 \times 0\):** 1. Notice that any number multiplied by \(0\) equals \(0\). Thus, \(87 \times 89 \times 0=0\) --- **n. Calculation of \(0 \times (236-137) \div 54\):** 1. Compute the expression in parentheses: \(236-137=99\) 2. Multiply: \(0 \times 99=0\) 3. Divide: \(0\div 54=0\) --- **o. Calculation of \(476 \times (-14+27-13)\):** 1. Simplify the expression in parentheses step by step: \(-14+27=13\) Then \(13-13=0\) 2. Multiply: \(476 \times 0=0\)