Mental Maths for Solving Arithmetic Word Problems Understanding Divisibility: Imagine dividing a number into specific parts, like evenly dividing 18 by 3...
Understanding Divisibility:
Imagine dividing a number into specific parts, like evenly dividing 18 by 3. The result tells you how many parts it has and the remaining number.
Divisibility Rules:
A number is divisible by 3 if it ends in 3 or 0.
A number is divisible by 4 if the last two digits are both even.
A number is divisible by 5 if the last digit is either 0 or 5.
A number is divisible by 6 if it ends in 0.
Applying Divisibility Rules:
Problem 1: If you have a number with 3 as a factor and you need to divide it by 4, it's divisible by 4.
Problem 2: Find the largest multiple of 3 that is less than 30. It's 15, so 15 is divisible by 3.
Understanding Decimals:
Decimals are a way of representing numbers with non-whole numbers and fractions.
Reading and Writing Decimals:
A number with a decimal point should be read as a fraction of 10 or 100.
0.25 is the same as 25/100.
Adding and Subtracting Decimals:
When adding or subtracting decimals with the same digits, they are added or subtracted in the place value they occupy.
0.34 + 0.12 = 0.46.
0.6 - 0.25 = 0.35.
Comparing and Ordering Decimals:
Compare decimals by placing them in order from smallest to largest.
0.12 is less than 0.23, which is less than 0.34.
Therefore, 0.12 comes before 0.23 and before 0.34.
Practice Makes Perfect:
Solve word problems involving division and decimals by applying the knowledge you've gained.
Start with simple problems and gradually progress to more complex ones.
Use manipulatives like blocks or counters to visualize division and addition with decimals