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Here’s and example of a Speed Math shortcut for SQUARING NUMBERS ENDING WITH 5 : (Sq) LD5dx

When can I use this method?

For squaring 2-digit numbers or 3-digit numbers ending with 5.

One can also use this method to solve higher digit numbers as long as multiplication of numbers is easy enough.

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Here’s and example of a Speed Math shortcut for MULTIPLYING NUMBERS WITH COMMON LAST DIGITS : (Mul) LDSdx

When can I use this method?

For multiplying any 2-digit number with another 2-digit number such that the last digit of the multiplier and multiplicand are same. The first digits can be different.

For multiplying any 3-digit number with another 3-digit number such that the last digit of the multiplier and multiplicand are same. The initial 2 digits can be different.

You can also use this method to multiply numbers with unequal number of digits, i.e. multiplying a 2-digit number with a 3-digit number such that the last digit of the multiplier and multiplicand are the same.

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Problem

In a partnership between A, B and C, A’s capital is $5000. If his share of profit of $800 is $200 and C’s share is $130, what is B’s capital?

1. $3250
2. $6250
3. $10250
4. $11750
5. Data Insufficient

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Here’s and example of a Speed Math shortcut for MULTIPLYING NUMBERS NEAR 1000 : (Mul) Nr1000

When can I use this method?

For multiplying numbers near 1000. The numbers can be either more than 1000 or less than 1000 or a combination of the two.

You may also use this method to multiply numbers a little farther away from 1000 as long as their differences from 1000 are easy to multiply.

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Problem

If a man walks to his office at 3/4^th of his usual rate, he reaches office 1/3^rd of an hour later than usual. How much time does he usually take to reach his office?

1. 1/2 hour
2. 1 hour
3. 1/4 hour
4. 3/2 hours
5. 2/3 hour

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Here’s and example of a Speed Math shortcut for MULTIPLYING WITH 6: (Mul) Nx6

When can I use this method?

For multiplying any number with 6.

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Here’s and example of a Speed Math shortcut for MULTIPLYING WITH 25: (Mul) Nx25

When can I use this method?

For multiplying any number with 25.

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Problem

Of an amount of $1500 divided between A, B and C, B’s share is $70 more than C’s and A’s share is $100 less than C’s. What is A’s share?

1. $410
2. $425
3. $450
4. $490
5. $510

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Here’s and example of a Speed Math shortcut for Squaring 2-digit Numbers ending with 1: (Sq) LD1d2

When can I use this method?

For squaring 2-digit numbers ending with 1.

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Problem

B invests $500 more than A in business, but A’s investment in the business is for 4 months, whereas B’s investment is for 3 months only. If A’s share of total profit of $520 is $40 more than B’s. How much did A contribute to business?

1. $2500
2. $3000
3. $3500
4. $4000
5. $4500

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