# 5th Grade - Work With Decimals And Negative Numbers

 Grade Level: 5th Skill: Fractions, Percentages and Decimals Topic: Work with Decimals and Negative Numbers Goal: Add, subtract, multiply, and divide with decimals; add with negative integers; subtract positive integers from negative integers; and verify the reasonableness of the results. Skill Description: Students must be able to do basic math functions with decimals. They also have to add and subtract positive and negative numbers. Because this standard is so large, it is usually taught over two/three months.

### Sample Problems

 (1) .763 x .429 (.327327) (2) .424 ÷ .4 (.1696) (3) (6) + (-5) (1) (4) (4) – (- 9) (13) (5) (-14) – (-12) (-2)

### Learning Tips

 (1) When solving a problem with decimals it helps to put the decimal in the correct spot of your answer BEFORE you do any computing. If students wait until they finish the problem to put the decimal, they are more likely to forget. (2) “in the black” and “in the red” are real-world examples of negative and positive numbers. Share what these phrases mean with your child, and ask them to use their allowance as an example of what in the red/black would mean in their life. (3) Decimals are a pretty simple step in mathematics to pick up. If your child is still struggling to find the correct answer, you will want to check that the actual computing is correct. If they are getting the numbers wrong and not the decimal place, chances are you will have to go back to the basics and review number sense before adding in decimals. (4) 5th grade is the first time students are seeing negative numbers, and although some catch on quickly, many, many others struggle. A number line helps the visual learners understand what it means to add and subtract negative and positive numbers. If your child is still struggling after using a number line, try using two-color chips. One side represents negative and the other color is positive. (5) A basic fundamental that students need to understand is the “zero-pair.” A negative and a positive cancel each other out. Again, the simplest way to show this to confused kids is to use two-color chips. At school we use red and yellow chips, with yellow the positive and red the negative. So, if I have 3 yellows and 3 reds I have 0, or three zero pairs. If I have 3 yellows and four reds I have -1 because I have three zero pairs and one extra negative chip.

### Online Resources

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### Extra Help Problems

 (1) .429 + .73 (1.159) (2) 84.36 + 9.8 (94.16) (3) 3.25 + 7.46 (10.71) (4) 14.26 + 26.14 (40.4) (5) 93.22 – 57.09 (36.13) (6) 8.62 – 4.63 (3.99) (7) .723 - .4 (.323) (8) .1 - .01 (.09) (9) .24 x 5.8 (1.392) (10) .71 x .64 (.4544) (11) 35 x 6.8 (238) (12) 7.14 x 3.29 (23.4906) (13) 588.8 / 2.3 (256) (14) 316.8 / 6.4 (49.5) (15) 189.735 / 3.5 (54.21) (16) 107.52 / 4.2 (25.6) (17) -12+6 (-6) (18) -5 + -6 (-11) (19) -3 + 8 (5) (20) -5 + -4 (-9) (21) 9 + -14 (-5) (22) -3 - +2 (-5) (23) 7 - -4 (11) (24) 6- -12 (18) (25) -4 - +7 (-11)