Estimate Quotients © 2007 M. Tallman

Compatible numbers are numbers that contain a basic division fact… When estimating division problems, rounding will not work very well. You must use compatible numbers. Compatible numbers are numbers that contain a basic division fact… …8,100 ÷90, 720 ÷ 8, 144,000 ÷ 120 © 2007 M. Tallman

Find the compatible numbers in these division problems. 1. 120 ÷ 4 2. 3. 21,000 ÷ 7 4. 240 ÷ 6 5. 6. 7. 320 ÷ 8 8. → 12 ÷ 4 → 36 ÷ 9 → 21 ÷ 7 → 24 ÷ 6 → 42 ÷ 7 → 35 ÷ 5 → 32 ÷ 8 → 96 ÷ 8 ) 9 3,600 7 ) 4,200 5 ) 35,000 8 ) 9,600 © 2007 M. Tallman

437 ÷ 9 45 ÷ 9 = 5 Estimating Quotients 1 1 1 - 0 = 1 1 zero in the quotient 1 - 0 = 1 1 1 45 ÷ 9 = 5 Step 1: Look at the first couple of numbers of the dividend and the first number of the divisor. Step 2: Find the closest basic division fact to these numbers. Step 3: Use the basic fact to change the dividend and divisor in to compatible numbers, and divide. © 2007 M. Tallman

508 ÷ 7 49 ÷ 7 = 7 Estimating Quotients 1 1 1 - 0 = 1 1 zero in the quotient 1 - 0 = 1 1 1 49 ÷ 7 = 7 Step 1: Look at the first couple of numbers of the dividend and the first number of the divisor. Step 2: Find the closest basic division fact to these numbers. Step 3: Use the basic fact to change the dividend and divisor in to compatible numbers, and divide. © 2007 M. Tallman

) 7 224 3 ) 7 21 Estimating Quotients 1 1 1 - 0 = 1 1 zero in the quotient 1 3 ) 7 21 1 - 0 = 1 1 Step 1: Look at the first couple of numbers of the dividend and the first number of the divisor. Step 2: Find the closest basic division fact to these numbers. Step 3: Use the basic fact to change the dividend and divisor in to compatible numbers, and divide. © 2007 M. Tallman

4,324 ÷ 6 4,2 ÷ 6 = 7 Estimating Quotients 1 2 1 2 2 - 0 = 2 2 zeros in the quotient 2 - 0 = 2 1 2 1 2 4,2 ÷ 6 = 7 Step 1: Look at the first couple of numbers of the dividend and the first number of the divisor. Step 2: Find the closest basic division fact to these numbers Step 3: Use the basic fact to change the dividend and divisor in to compatible numbers, and divide. © 2007 M. Tallman

) 4 3,105 8 ) 4 3,2 00 Estimating Quotients 1 2 1 2 2 - 0 = 2 2 zeros in the quotient 1 2 8 ) 4 3,2 00 2 - 0 = 2 1 2 Step 1: Look at the first couple of numbers of the dividend and the first number of the divisor. Step 2: Find the closest basic division fact to these numbers. Step 3: Use the basic fact to change the dividend and divisor in to compatible numbers, and divide. © 2007 M. Tallman

) 5 4,175 8 ) 5 4,0 00 Estimating Quotients 1 2 1 2 Tip: Do not count the zero in 40. 2 zeros in the quotient 1 2 8 ) 5 4,0 00 2 - 0 = 2 1 2 Step 1: Look at the first couple of numbers of the dividend and the first number of the divisor. Step 2: Find the closest basic division fact to these numbers. Step 3: Use the basic fact to change the dividend and divisor in to compatible numbers, and divide. © 2007 M. Tallman

Division Fact:_________ Estimate:____________ 48 ÷ 8 = 8 Your Turn Estimate 468 ÷ 8 Division Fact:_________ Estimate:____________ 48 ÷ 8 = 8 480 ÷ 8 = 80 © 2007 M. Tallman

Division Fact:_________ Estimate:____________ Your Turn Estimate Division Fact:_________ Estimate:____________ 5,620 ÷ 5 55 ÷ 5 = 11 5,500 ÷ 5 = 1,100 © 2007 M. Tallman

Division Fact:_________ Estimate:____________ Your Turn Estimate Division Fact:_________ Estimate:____________ 2,198 ÷ 4 20 ÷ 4 = 5 2,000 ÷ 4 = 500 © 2007 M. Tallman

Division Fact:_________ Estimate:____________ Your Turn Estimate Division Fact:_________ Estimate:____________ 358 ÷ 12 36 ÷ 12 = 3 360 ÷ 12 = 30 © 2007 M. Tallman

Division Fact:_________ Estimate:____________ Your Turn Estimate Division Fact:_________ Estimate:____________ 1,976 ÷ 9 18 ÷ 9 = 2 1,800 ÷ 9 = 200 © 2007 M. Tallman